Written reply of the African Union to the questions put by the Court

OBLIGATIONS OF STATES IN RESPECT OF CLIMATE CHANGE
(REQUEST FOR ADVISORY OPINION)
THE AFRICAN UNION’S
ANSWERS TO THE
QUESTIONS FROM THE
COURT
20 December 2024
TABLE OF CONTENTS
I – Preliminary remarks .................................................................................................... 3
II – The African Union’s Answers to the Questions ....................................................... 4
A. The First Question ................................................................................................................... 4
1. Differentiation ....................................................................................................................................... 4
2. Sustainable development ...................................................................................................................... 8
3. Conclusion .............................................................................................................................................. 9
B. The Second Question ............................................................................................................... 9
1. Object and purpose of the Paris Agreement ....................................................................................... 10
2. Object and purpose of the UNFCCC ................................................................................................... 12
3. The interpretation of Article 4 ............................................................................................................ 13
C. The Third Question ................................................................................................................ 15
D. The Fourth Question ............................................................................................................. 20
1. Context of the Declarations ................................................................................................................. 21
2. Significance of the Declarations ......................................................................................................... 23
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I – PRELIMINARY REMARKS
1. Following its participation in the written and oral phases of these advisory
proceedings before the International Court of Justice (the “Court”),1 the African
Union is honoured to be given a further chance to assist the Court, by answering four
questions posed by its distinguished members.
2. In its Written Statement, the African Union stressed that these proceedings,
important as they are on the global stage, have an existential character for African
states and peoples2 – which stand amongst those most affected by climate change,
despite contributing the least to it.3 In its Written Comments, the African Union was
encouraged to see a convergence of views amongst a majority of states in how to
approach the questions posed by the General Assembly in Resolution 77/276. 4
Nonetheless, it noted with concern that a minority of participants have urged the
Court – mistakenly – to exercise undue restraint and refrain from providing the clear,
concrete, and authoritative answers that the questions demand.5
3. The African Union’s participation in the oral proceedings was thus driven by a single,
overriding goal: to underscore the central importance of climate justice for this
Advisory Opinion6 This principle, the African Union argued, is not merely aspirational
but can and must be operationalized – most notably through initiatives such as debt
cancellation or relief for the world’s most vulnerable states.7
4. Against that background, the African Union views all four questions posed by the
Court as striking at the core of the matter. Each deserves answers that will
meaningfully assist the Court in rendering its Advisory Opinion. The present
submission seeks to provide such answers.
1 All abbreviations and acronyms in these Answers are carried over from the Written Statement of the African Union, dated 22 March 2024
(“WS”), and the Written Comments of the African Union, dated 15 August 2024 (“WC”).
2 See for example WS, para. 151.
3 African Union’s Expert Report, Dr. Christopher Trisos, “Evidence of Observed Impacts from Human-Induced Climate Change, and Projected
Future Impacts on Africa” (22 March 2024), para. 20.
4 See for example WC, paras. 3 and 67.
5 Ibid., para.4.
6 Verbatim Record 2024/44, p. 57 (African Union).
7 Verbatim Record 2024/44, p. 71 (African Union).
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II – THE AFRICAN UNION’S ANSWERS TO THE
QUESTIONS
A. THE FIRST QUESTION
5. The question put by Judge Cleveland is as follows:
During these proceedings, a number of participants have referred to the
production of fossil fuels in the context of climate change, including with
respect to subsidies. In your view, what are the specific obligations under
international law of States within whose jurisdiction fossil fuels are produced
to ensure protection of the climate system and other parts of the environment
from anthropogenic emissions of greenhouse gases, if any?
6. Given that fossil fuel production (coal, gas and oil) is the main cause of climate
change,8 the African Union welcomes this opportunity to clarify the obligations of
states within whose jurisdiction fossil fuels are produced (hereafter “fossil fuel
producing states”).
7. In what follows, the African Union submits that these obligations are to be identified
and interpreted in light of the guiding principles proposed by the African Union in its
oral pleadings, i.e., taking into account (i) differentiation, and (ii) sustainable
development as foundational norms of customary international law.9
1. Differentiation
8. The duties of all fossil fuel producing states arise from the due diligence duty to protect
the climate system and other parts of the environment in light of the best available
science.10 To discharge their duty, States must evaluate the costs and benefits of
producing fossil fuels and take reasonable steps to move to renewable sources of
energy.11 The level of diligence expected will vary in accordance with the risk to the
8 IPCC, Synthesis Report of the IPCC Sixth Assessment Report (AR6), Summary for Policymakers, statement A.1, available at
https://www.ipcc.ch/report/sixth-assessment-report-cycle/.
9 Verbatim Record 2024/44, p. 69 (African Union), para 22.
10 See for example, Glasgow Climate Pact, para. 6 (the same text was adopted by the Meeting of the Parties of the Paris Agreement in Decision
1/CMA.3, para. 7).
11 See for example, Decision 1/CMA.5 ‘Outcome of the first global stocktake’ (2023), para. 28.
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climate system represented by each category of fossil fuel, as well as the level of
development of the producing state.12
9. There is no unified category of “fossil fuel producing states” under international law.
Instead, the principle of Common but Differentiated Responsibilities and Respective
Capabilities (“CBRD-RC”), as stated in the Paris Agreement, dictates that developed
countries must take the lead in phasing out fossil fuels.13 The African Union reiterates
its request that the Court confirms that the CBDR-RC principle has achieved
customary status.14 It is uncontested that developed countries are both the biggest
emitters of greenhouse gas emissions and the largest producers of fossil fuels. By
virtue of their historical responsibility and current capabilities, they must display a
higher level of diligence with the view to phasing out fossil fuels. As UNEP’s 2023
Production Gap Report notes:
Not all countries can phase out fossil fuels at the same pace. Countries that
have higher financial and institutional capacity and are less dependent on
fossil fuel production can transition most rapidly, while those with lower
capacity and higher dependence will require greater international support.
They will require assistance and finance to pursue alternative development
models.15
10. As a result, developed countries are under the duty to stop the expansion of fossil fuel
projects on their territory. The customary duty to prevent significant harm16 as well
as the treaty obligations set by the Paris Agreement cannot be met by perpetuating
reliance on fossil fuels, such as opening new fossil fuel operations. According to the
Intergovernmental Panel on Climate Change (“IPCC”), CO2 emissions expected to
occur over the lifetime of existing fossil fuel infrastructure already exceeds the
remaining 1.5°C carbon budget.17 As a result, the International Energy Agency has
12 For example, as stated in its decision “it is the view of the Court that it is for each State to determine in its domestic legislation or in the
authorization process for the project, the specific content of the environmental impact assessment required in each case, having regard to the
nature and magnitude of the proposed development and its likely adverse impact on the environment as well as to the need to exercise due
diligence in conducting such an assessment”. Pulp Mills on the River Uruguay (Argentina v. Uruguay), Judgment, I.C.J. Reports 2010, p. 14,
para. 205.
13 Paris Agreement, Article 4 (4) .
14 Verbatim Record 2024/44, p. 70 (African Union), para. 23.
15 UNEP, Production Gap Report 2023, p. 14.
16 International courts and tribunals recognized the ‘no-harm principle’ as customary international law. See, e.g., Trail smelter (United States
v. Canada), III RIAA 1905, 1965 (Perm. Ct. Arb. 1941); Legality of the Threat or Use of Nuclear Weapons, Advisory Opinion, 1996 ICJ Rep
226, para 29.
17 IPCC, Summary for Policymakers 2023, B.5.
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warned that there is “no room for new coal mines, oil and gas fields, or fossil-fuelburning
power plants”.18
11. The collective acknowledgement of this situation is reflected in the commitment of the
COP “to a fair and accelerated process of phasing down unabated coal power”,19
reiterated by the African Union in its Nairobi Declaration.20 Moreover, domestic
courts worldwide have found the expansion of fossil fuel projects in developed
countries to be incompatible with the protection of the climate, including on the basis
of the net zero objective of the Paris Agreement.21 Finally, this duty is confirmed by
the emerging consensus among human rights treaty bodies that developed countries
should phase out fossil fuels in order to minimise their human rights impacts.22
12. The duty to exercise due diligence to prevent significant harm includes a duty to
assess, as well as continuously monitor, environmental harm from Greenhouse gas
(“GHG”) emissions linked to fossil fuel production, through in particular, impact
assessments. 23 Impact assessments should include an evaluation of scope of
emissions of fossil fuel projects which attributes GHG emissions from the burning of
fossil fuels to the exporter of the product. This is necessary to fully account for climate
impacts, as acknowledged by domestic courts.24 In addition, they should take into
consideration the human rights impacts of fossil fuel exploitation on local
communities.25
13. Reasonable steps to act with due diligence includes discontinuing financial incentives
and investments in favour of fossil fuels. The IPCC has found that fossil fuel subsidy
18 IEA, Net Zero by 2050: A Roadmap for the Global Energy Sector (2021)
19 Decision 1/CP.26, ‘Glasgow Climate Pact’, para 20; Decision 1/CP.27, Sharm-el-Sheikh Implementation plan, para. 13.
20 Nairobi Declaration, para. 19.
21 Gloucester Resources Limited v. Minister for Planning [2019] NSWLEC 7 (Australia), para 525-6; Friends of the Earth v. West Cumbria
Mining [2024] EWHC 2349 (Admin) (United Kingdom).
22 Joint Statement on Human Rights and Climate Change (2019), para. 3; Concluding observations on the eighth periodic report of Australia,
25 July 2018, CEDAW/C/AUS/CO/8, para. 30(c); Concluding observations on the tenth periodic report of Norway, 2 March 2023,
CEDAW/ C/NOR/CO/10, paras. 48(b)-(c) and 49(a)-(b); Concluding observations on the combined fifth and sixth periodic reports of
Azerbaijan, 22 February 2023, CRC/C/AZE/CO/5-6, para. 14(c); UN Special Rapporteurs, “Statement: Fossils fuels at the heart of the
planetary environmental crisis: UN experts” (30 November 2023).
23 Paris Agreement, Article 4(2) and 7 (9). See also B Mayer, ‘Climate Assessment as an Emerging Obligation under Customary International Law’
(2019) 68(2) International and Comparative Law Quarterly 271-308.
24 Gray v. Minister for Planning and Ors [2006] 152 LGERA 258 (Australia); KEPCO Bylong Australia v. Independent Planning Commission
and Bylong Valley Protection Alliance [2020] NSWLEC 179 (Australia); Greenpeace Nordic and Nature & Youth v. Energy Ministry,
Application no. 23-099330TVI-TOSL/05, [2024] Oslo District Court (Norway); Finch v. Surrey County Council [2024] UKSC 20 (United
Kingdom).
25 Social and Economic Rights Action Centre (SERAC) and the Centre for Economic and Social Rights (CESR) v. Nigeria 2002; Gbemre v. Shell
Petroleum Development Company of Nigeria Ltd. and Others (2005) FHC/B/CS/53/05.
7
removal is projected to reduce global emissions,26 and the COP has committed to
“phase out of inefficient fossil fuel subsidies”.27 Developed States are under a duty to
take the lead in phasing out fossil fuel subsidies, as well as diverting investments
towards sustainable sources of energy. 28 Reform of fossil fuel subsidies need to
consider domestic contexts, including the social costs for vulnerable and poor
populations in developing countries.29
14. Further, the duty to prevent environmental harm requires vigilance vis-à-vis the
activities of private operators.30 On the African continent, two thirds of the projected
new gas and oil production are carried out and financed by foreign companies, most
of them headquartered in developed countries, 31 just as the vast majority of
institutional investors backing fossil fuel expansion in Africa.32 As a result, states
where fossil fuel producing companies are headquartered should regulate their
activities to ensure they do not produce harm to the climate or to human rights.33
15. In addition, developed countries are under a duty to support developing countries to
decarbonise and diversify their economy.34 The level of due diligence required of fossil
fuel producing developing states is conditional upon receiving assistance to move
away from fossil fuel production used for internal demand as well as exports.
Developed countries should offer “support towards a just transition”, including by
“providing targeted support to the poorest and most vulnerable in line with national
circumstances”, as called for by the Nairobi Declaration.35 Moreover, Article 9 of the
Paris Agreement obliges developed countries, to “provide financial resources to assist
developing countries with adaptation and mitigation”.36
16. Finally, the obligations of fossil fuel producing states extend to their duties under the
law of State responsibility to cease wrongful conduct and guarantee its non-recurrence,
which means, inter alia, halting the expansion of fossil fuel projects and rapidly
26 IPCC, Summary for Policy-Makers (2023), para. C.6.4.
27 Glasgow Climate Pact, para 20; Sharm-el-Sheikh Implementation plan, para. 13
28 Joint Statement on Human Rights and Climate Change (2019), para. 3.
29 ‘In Africa, governments cut back on fuel subsidies’ (Le Monde, 13 October 2023).
30 Verbatim Record 2024/44, p. 68 (African Union), para. 21.
31 Heffa Schuecking et al., Who is Financing Fossil Fuel Expansion In Africa? (2022), p 15.
32 Ibid., p. 41
33 Joint Statement on Human Rights and Climate Change (2019), para. 3.
34 Paris Agreement, Article 4 (5).
35 Nairobi Declaration, para. 19(iii).
36 Paris Agreement, Article 9; UNFCCC, Article 4 (3).
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phasing out fossil fuels. In application of the polluter-pays principle,37 developed
countries producing fossil fuels are under a duty to repair and compensate for the
damage suffered.38
2. Sustainable development
17. The duties of fossil fuel producing states in developing countries need to be interpreted
in light of the principle of sustainable development, that is, in light of the “need to
reconcile economic development with protection of the environment”.39 The African
Union reiterates its request for the Court to recognize the right to sustainable
development as a customary norm of international law. 40
18. The customary right to permanent sovereignty over natural resources,41 the right and
duty to promote sustainable development under the UNFCCC,42 and the objective of
the Paris Agreement to fight climate change in the “context of sustainable
development and efforts to eradicate poverty”,43 all point to the same obligation:
developing countries have a duty to develop in a sustainable manner, that can be
carried out by producing fossil fuels to meet internal demand and grow economically.
19. Developing countries must take into account their commitment to contribute to
Sustainable Development Goal 7 on universal access to affordable energy by 2030,
including to the 600 million lacking access to electricity and 970 million lacking access
to clean cooking in Africa.44 Africa accounts for less than 3% of the world’s energyrelated
CO2 emissions to date and has the lowest emissions per capita of any region.45
Even if Africa were to increase its use of fossil fuels, including gas, this would bring
its share of global emissions to “a mere 3.5%”,46 while reducing extreme poverty levels.
20. As such, in application of the principle of sustainable development, the duties of fossil
fuel producing developing states will vary depending on the economic and social
benefits arising from energy production. This remains compatible with the recognition
37 Rio Declaration on Environment and Development (1992), Principle 16. See Written Statement of Switzerland, para 78.
38 Paris Agreement, Article 4(4), UNFCC, Article 4(3
39 Gabčíkovo-Nagymaros Project (Hungary/Slovakia), Judgment, I.C.J. Reports 1997, para. 140.
40 Verbatim Record 2024/44, p. 70 (African Union), para. 23.
41 African Union, Written statement, para 198.
42 UNFCCC, Article 3(4).
43 Paris Agreement, Article 2(1)
44 IEA, Africa Energy Outlook 2022, p. 16.
45 IEA, Africa Energy Outlook 2022, p. 15
46 IEA, Africa Energy Outlook 2022, p. 17.
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that all States will progressively need to move away from their reliance on fossil fuel
and diversify their energy mix and economic policies.
3. Conclusion
21. To conclude, the reality of fossil fuel production, exploitation and financing means
that the obligations of fossil fuel producing states vastly align with that of developed
countries. This convergence highlights the shared responsibility under international
law to address the environmental and social impacts of fossil fuel production. Climate
justice, as reflected in key international legal frameworks, must therefore once again
guide the Court in its identification of the obligations of fossil fuel producing states.47
B. THE SECOND QUESTION
22. The question put by Judge Tladi is as follows:
In their written and oral pleadings, participants have generally engaged in
an interpretation of the various paragraphs of Article 4 of the Paris
Agreement. Many participants have, on the basis of this interpretation, come
to the conclusion that, to the extent that Article 4 imposes any obligations in
respect of Nationally Determined Contributions, these are procedural
obligations. Participants coming to this conclusion have, in general, relied on
the ordinary meaning of the words, context and sometimes some elements in
Article 31 (3) of the Vienna Convention on the Law of Treaties. I would like
to know from the participants whether, according to them, “the object and
purpose” of the Paris Agreement, and the object and purpose of the climate
change treaty framework in general, has any effect on this interpretation and
if so, what effect does it have?
23. This question goes straight to what the African Union has identified in its written
submissions: the effort by some states and participants to dilute the principles at
stake and steer the Court’s answers towards vague, uncontroversial conclusions that
avoid meaningful accountability.
24. Instead, it is clear that the object and purpose of the relevant instruments underscore
that Article 4 of the Paris Agreement is a key part of the obligations of states in respect
of climate change, and should be given significant weight in the Court’s answers to
the General Assembly’s questions.
47 Verbatim Record 2024/44, p. 67 (African Union), para. 16.
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25. Before answering this question, however, it is important to stress that an
interpretation which seeks to limit Article 4 of the Paris Agreement to mere
procedural obligations is neither universally shared, nor consistent with the treaty’s
broader framework. Be it in their written submissions,48 or during the oral phase of
the proceedings,49 many states and participants have stressed the centrality of this
provision to the overriding goal of fighting climate change, 50 and read it as
encompassing binding mitigation measures that reflect each state’s duty of care.51
1. Object and purpose of the Paris Agreement
26. In accordance with Article 31(3) of the Vienna Convention on the Law of Treaties
(“VCLT”), any good faith interpretation of the Paris Agreement, based on the ordinary
meaning of its terms and in their context, must first and foremost, take into account
its object and purpose as per Article 31 (1) VCLT.
27. Traditionally, the object and purpose of an international instrument such as the Paris
Agreement is found in (i) its preamble, which provides context for the treaty’s aims
and guiding principles; and (ii) any provision that explicitly defines the treaty’s
objectives, such as Article 2 and 4(1) of the Paris Agreement.52
28. The Preamble of the Paris Agreement reaffirms the urgent need for global
cooperation to combat climate change. It explicitly references key principles that
underscore its object and purpose, including sustainable development,
intergenerational equity, and the importance of limiting global temperature increases
to protect humanity and ecosystems. It also underlines the need to steer and assess
actions “on the basis of the best available scientific knowledge”.
29. Article 2 of the Paris Agreement explicitly articulates the Paris Agreement’s aims,
notably:
48 See, e.g., the Written Statements of Colombia, para. 3.35; Netherlands, para. 3.14.
49 Verbatim record CR 2024/36, p. 62 (Bahamas), para. 20 (“These NDCs are not an aspirational wish list, or a purely discretionary decision, or
an unguided exercise. Their setting is a matter of concrete, binding obligations.”).
50 Written Statements of Australia, para. 2.18, and USA, para. 3.9, describing Article 4 as “the heart” of the Paris Agreement and the “UN climate
change regime”. See also WS, para. 131; Written Statement of the Seychelles, para. 70 (“Article 4.2, known as the key provision of the treaty”);
Vanuatu, para. 409; Verbatim Record 2024/41, p. 10 (France), para. 12.
51 Written Statement of China, para. 50; Seychelles, para. 96 (“These are concrete obligations, not merely platonic ones, which are consistent with
the climate change risks”); Vanuatu, para. 409.
52 Other participants have also focused on these provisions as reflecting the Paris Agreement’s object and purpose. For Article 2, see, e.g., Verbatim
record CR 2024/36, p. 62 (Bahamas), para. 21. For Article 4(1), see, e.g., Written Statement of the United Kingdom, paras. 19-20; Latvia,
para. 29.
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a. Holding the increase in global average temperature well below 2°C above preindustrial
levels, and pursuing efforts to limit the temperature increase to
1.5°C;
b. Enhancing the ability to adapt to adverse impacts of climate change and foster
climate resilience; and
c. Aligning financial flows with low greenhouse gas emissions and climateresilient
development.
These objectives reflect the Paris Agreement’s comprehensive and dynamic 53
approach to addressing climate change.
30. Article 4(1) of the Paris Agreement, meanwhile, builds on the goals laid out in
Article 2, by:
a. Repeating “the long-term temperature goal set out in Article 2”;
31. Requiring states to pursue the “global peaking of greenhouse gas emissions as soon as
possible”, while acknowledging differentiated timelines for individual countries;
a. Calling for rapid emission reductions thereafter, guided by the best available
science; and
b. Reaffirming the Agreement’s commitment to equity, sustainable development,
and poverty eradication.
32. Together, these provisions underscore that the Paris Agreement’s object and purpose
cannot be satisfied by a narrow, procedural reading of Article 4 as it clearly also
imposes substantive obligations.
33. To summarise, several key elements that define the Paris Agreement’s object and
purpose reflect substantive obligations of conduct such as:
a. Advancing the framework established by the UNFCCC;
53 Written Statement of the IUCN, para. 134 (“The references to CBDR-RC in the Preamble and Articles 2(2) and 4(3) indicate that the Paris
Agreement should be implemented in a manner that is not static, but open to change. Its general, principled character allows the Parties’
obligations to respond to evolving understandings of accountability for temperature increases and changing political, social and economic
circumstances for holding them to 1.5oC. Responsibilities, capabilities and national circumstances differ significantly and are in flux. Thus, they
should be taken into account in a dynamic fashion.”)
12
b. Operationalizing a temperature goal that requires significant and substantive
commitments from states;
c. Encouraging a progressive and differentiated approach, allowing obligations
to evolve; and
d. Orient each state’s actions in light of the best available scientific evidence.
2. Object and purpose of the UNFCCC
34. In accordance with Article 31(3) of the VCLT, the Paris Agreement operates within
the broader framework of the UNFCCC, whose object and purpose it explicitly seeks
to advance. This connection is evident in the Paris Agreement’s Preamble and
substantive provisions, which frequently reference the UNFCCC. In turn, Article 2 of
the UNFCCC specifies that the object and purpose of this instrument extends to “any
related legal instruments that the Conference of the Parties may adopt”. Moreover,
Article 4 of the Paris Agreement echoes and builds upon Articles 4(1)(b) and 4(2)(a) of
the UNFCCC, which provide for the obligation of developing and developed state
Parties to adopt and implement national policies, programmes and measures to
mitigate climate change. 54 The UNFCCC is thus of utmost relevance to the
interpretation of the Paris Agreement.
35. The UNFCCC, in its Preamble and Article 2, emphasizes the stabilization of
greenhouse gas concentrations to prevent dangerous anthropogenic interference with
the climate system. It hinges upon the dangers represented to “anthropogenic
interference with the climate system” – dangers that have only become more concrete
as time passes. The treaty further identifies common but differentiated
responsibilities (“CBDR”) and respective capabilities as guiding principles, alongside
the need for sustainable development.55
36. The Paris Agreement must therefore be interpreted in light of the UNFCCC’s
foundational aim: to ensure effective, equitable, and science-based international
cooperation to combat climate change.
54 Written Statement of Ecuador, para. 3.80.
55 As explained by the African Union in its submissions, CBDR and sustainable developments are principles that are now part of customary
international law: see Verbatim Record 2024/44, p. 69 (African Union), paras. 22-23.
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3. The interpretation of Article 4
37. Viewed through the lens of the object and purpose of both the Paris Agreement and
the UNFCCC, Article 4 is far more than a procedural mechanism – it imposes binding
obligations of conduct that require states to undertake substantive efforts toward
mitigation.56 This is reflected in its various subparagraphs, which “must, like any
other legal text, be read as a whole”.57
38. Article 4(1)’s opening language directly ties this central provision to the long-term
temperature goal set out in Article 2,58 and therefore to the Agreement’s object and
purpose. In essence, Article 4(1) operationalizes the Agreement’s overarching aims
through the commitments set out in the rest of the article. This is further confirmed
by Article 3 of the Paris Agreement, which obliges states to “undertake and
communicate ambitious efforts as defined in Articles 4, 7, 9, 10, 11 and 13 with the
view to achieving the purpose of this Agreement as set out in Article 2”.59 The term
“undertakes” is particularly important, as it implies an obligation of conduct.60
39. Article 4(2) then contains two categories of commitments corresponding to the
provision’s two sentences. The first obliges states to “prepare, communicate, and
maintain” Nationally Determined Contributions (“NDCs”) with the aim of achieving
the Agreement’s objectives.61 The second obliges states to “pursue domestic mitigation
measures, with the aim of achieving the objectives of such contributions.”62
40. Article 4(3), in turn, reinforces the principle of progression, mandating that NDCs
reflect each state’s “highest possible ambition” and represent a clear advancement
beyond previous contributions.63 The notions of progression and “highest possible
56 WS, para. 132 (“Article 4(2) sets the binding procedural obligation to communicate an NDC as well as the binding substantive obligation to
pursue domestic measures with the aim of achieving the objectives of the NDC”); Written Statement of the Seychelles, para. 71.
57 Admissibility of Hearings of Petitioners by the Committee on South West Africa, Advisory Opinion, 1 June 1956, Separate Opinion of Sir
Hersch Lauterpacht, p. 44.
58 WS, para. 51. Written Statement of Singapore, paras. 3.35(a) (“while paragraph 2 gives Parties discretion in the specific domestic mitigation
measures they implement, they must nevertheless pursue these measures with the aim of achieving the objectives of their NDCs. A Party that
takes no steps or fails to take reasonable steps to do so violates Article 4(2).”) and 4.7; IUCN, para. 148 (“If a Party takes no measure, this
would violate that provision.”). See also Written Comments of Mauritius, para. 42.
59 Written Statement of Singapore, para. 35(a); Timor-Leste, paras. 110-116.
60 Written Statement of Tonga, paras. 149-152.
61 WS, para. 132.
62 Written Statements of the European Union, para. 154; Tonga, paras. 147-148; Vanuatu, para. 409. Verbatim Record 2024/48, p. 47 (United
Kingdom), para. 18.
63 Written Statement of China, para. 49.
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ambition” function together and are interconnected, 64 aligning with the Paris
Agreement’s goal of fostering a dynamic and adaptive climate regime. Article 4(3)
further refers to the key principle of CBDR, which demand substantive action from
all states, albeit differentiated based on their circumstances and capabilities.65 Both
principles – progression and CBDR – echo the Paris Agreement’s object and purpose,
and function in a self-reinforcing manner.66
41. Against the weight of these provisions, the claim that Article 4 is predominantly, if
not entirely, procedural stems from a misreading of the provision and a failure to
adhere to a holistic approach to treaty interpretation, which requires consideration of
both the context and the instrument’s object and purpose.
42. In particular, this claims ignores the second sentence of Article 4(2), which provides
for an obligation to undertake measures “with the aim of achieving the objectives”,67
an obligation that must be given full weight.68 Many states have rightly pointed out
that this entails an obligation of due diligence,69 the standard of which must be
assessed in light of each state’s duty of care, informed by three key consideration:
a. “the best available science”.70 As stressed by the African Union in its written
submissions and its expert report,71 science does indicate that the dangers and
risks are enormous,72 necessitating a high standard of care.73
64 Written Statement of the Seychelles, para. 75; European Union, para. 149.
65 WS, paras. 104(b), 131-133. Written Statements of Egypt, paras. 145-149.
66 C. Voigt & F. Ferreira, ‘‘Dynamic Differentiation’: The Principles of CBDR-RC, Progression and Highest Possible Ambition in the Paris
Agreement’ (2016) 5Transnational Law 2, 285-303, p. 303 (“Given the important role that differentiation has to play, it can be stated safely
that the Paris Agreement has succeeded in using differentiation as a means for enhancing ambition, as opposed to stalemating it. Rather than
setting countries apart, differentiation could become a tool for bringing countries closer together in serving the purpose of the Agreement.”)
67 Written Comments of the IUCN, para. 20 (commenting that “This obligation is critical to the good functioning of the Paris Agreement. States’
domestic mitigation measures must be calibrated to achieving the objectives of NDCs”); Kenya, paras. 4.51-4.52 (“Without any link to the
progressive attainment of the treaty’s objects and purposes, NDCs would be of limited relevance to the Paris Agreement.”)
68 Written Statements of the IUCN, para. 148 (“The achievement of the NDC itself does not become legally binding, but a State must pursue
measures that are coherent with the purpose of the NDC and rationally related to it.”); Colombia, para. 3.30.
69 WS, para. 133. See also Written Statements of Ecuador, para. 3.80; the European Union, para. 159; United Kingdom, paras. 22 and 23;
Singapore, para. 4.7; Seychelles, paras. 76-78; Timor-Leste, para. 119. Written Comments of Colombia, para. 3.30 (“the fact that Article 4(2)
is an obligation of conduct does not imply that States are exempt from sanctions if their domestic mitigation measures fall short of their objectives.
Instead, while external circumstances beyond the State’s control may be factored, such conduct will be assessed against the due diligence standard,
including the obligation to demonstrate progression over time.”).
70 WS, para. 96, citing in particular Responsibilities and obligations of States with respect to activities in the Area, Advisory Opinion, 1 February
2011, ITLOS Reports 2011, p. 10, para. 117: “‘due diligence’ is a variable concept. It may change over time as measures considered sufficiently
diligent at a certain moment may become not diligent enough in light, for instance, of new scientific or technological knowledge.”
71 WS, Expert Report of Dr. Trisos.
72 Written Statement of the Seychelles, paras. 81-85.
73 Written Statements of the IUCN, para. 136; Solomon Islands, paras. 80-82. Verbatim Record 2024/41, p. 11 (France), para. 15.
15
b. The key principle of progressive development, as embodied in Articles 3 and
4(3)’s reference to each state’s “highest possible ambition”.74
c. The principle of CBDR, 75 which finds echo in Article 4(4)’s call for the
leadership of developed countries.
These three considerations – science, progression, and CBDR – are integral to
achieving the Paris Agreement’s and the UNFCCC’s object and purpose: fostering
science-based, progressive, and differentiated efforts aimed at reaching the long-term
temperature goal.
43. These considerations are also relevant for the parties’ obligations under the first
sentence of Article 4(2): they will inform what NDCs states should prepare,
communicate, and maintain, in light of their particular situation and the principle of
progression and “highest possible ambition”.76 In other words, these considerations
“import substantive and qualitative elements into what on the face of it appears to be
a purely procedural obligation.”77
44. Consequently, reducing Article 4 to a procedural formality, particularly for developed
countries, not only misrepresents its intent but also undermines the overarching goals
of the Paris Agreement and the climate change treaty framework. Failing to recognize
the existent substantive obligations of this article risks weakening the collective effort
to combat climate change.
C. THE THIRD QUESTION
45. The question put by Judge Aurescu is as follows:
Some participants have argued, during the written and/or oral stages of the
proceedings, that there exists the right to a clean, healthy and sustainable
environment in international law. Could you please develop what is, in your
view, the legal content of this right and its relation with the other human
rights which you consider relevant for this advisory opinion?
74 Written Statement of Colombia, para. 3.39. Verbatim Record 2024/41, p. 11 (France), paras. 13-14 (“l’interprétation de ces obligations doit
refléter l’ambition des États en la matière, ce qui exige un niveau élevé de diligence dans leur mise en oeuvre”).
75 Written Comments of Mauritius, paras. 48-49. Verbatim Record 2024/41, p. 12 (France), para. 17.
76 WS, para. 133.
77 Written Statement of Vanuatu, para. 411.
16
46. All life depends on a safe, clean, healthy and sustainable environment. First
recognized in the 1972 Stockholm Declaration, 78 and reiterated in the 1992 Rio
Declaration,79 the right to a clean, healthy, and sustainable environment has recently
been acknowledged as a universal human right by the UN General Assembly
(“UNGA”)80 and the UN Human Rights Council (“HRC”).81 The judges of this Court
have also referred to the right.82
47. As regards its legal foundations, as argued by the African Union in its written
statement, the African continent, in particular, has been at the forefront globally in
recognizing the right to a clean, healthy and sustainable environment. 83 The African
Charter was indeed the world’s first regional human rights treaty to recognize it.84
According to its Article 24: ‘All peoples shall have the right to a general satisfactory
environment favorable to their development.’ Similarly, the 2003 Protocol to the
African Charter on the Rights of Women in Africa states that women ‘shall have the
right to live in a healthy and sustainable environment’.85
48. The African Union submits that the right to a clean, healthy and sustainable
environment finds recognition in treaties and it is also consolidating in customary
international law.86 The latter outcome is demonstrated by: (i) the adoption of the
resolutions by the UNGA and UN HRC that recognize the right to a sustainable,
healthy, and clean environment (with no states voting against either resolution);87 (ii)
statements made by various States discussing the right during the Universal Periodic
78 Report of the UN Conference on the Human Environment, Stockholm, 5–16 June 1972, A/CONF.48/14/Rev.1 (Stockholm Declaration),
principle 1.
79 Report of the United Nations Conference on Environment and Development, Rio de Janeiro, 3-14 June 1992, vol. I, Resolutions Adopted by
the Conference (UN publication, Sales No. E.93.I.8 and corrigendum) (Rio Declaration).
80 The human right to a clean, healthy and sustainable environment, UNGA Resolution 76/300, adopted 28 July 2022, A/RES/76/300.
81 The human right to a clean, healthy and sustainable environment, HRC Resolution 48/13, adopted 8 October 2021, A/HRC/RES/48/13.
82 Pulp Mills on the River Uruguay (Argentina v. Uruguay), Separate Opinion of Judge Cançado Trindade, I.C.J. Reports 2010), pp. 178, 184,
194, paras. 117, 132, 159 (references to “right to a healthy environment”); see Gabčíkovo-Nagymaros Project (Hungary/Slovakia), Separate
Opinion of Vice-President Weeramantry, I.C.J. Reports 1997, pp. 89-90 (references to “right to environmental protection” and “right to the
protection of the environment”).
83 WS, paras. 68, 69 and 192.
84 African Charter on Human and Peoples’ Rights (adopted 27 June 1981, entered into force 21 October 1986) CAB/LEG/67/3 rev. 5, ILM 58.
85 Protocol to the African Charter on Human and People's Rights on the Rights of Women in Africa, African Union, 11 July 2003, Articles 18
and 19.
86 William Schabas, The Customary International Law of Human Rights (Oxford University Press, 2021), p. 335.
87 The human right to a clean, healthy and sustainable environment, Human Rights Council Resolution 48/13, adopted 8 October 2021,
A/HRC/RES/48/13 (adopted with 43 votes in favour, 4 abstentions, 0 votes against); The human right to a clean, healthy and sustainable
environment, UNGA Resolution 76/300, adopted 28 July 2022, A/RES/76/300 (adopted with 161 votes in favour, 8 abstentions, 0 votes
against).
17
Review process;88 (iii) the presence of the right in numerous significant human rights
treaties; 89 (iv) the recognition of the right to a clean, healthy and sustainable
environment in States’ national constitutions, 90 legislation, court decisions and
regional treaties; 91 and (v) the recognition of the right to a clean, healthy and
sustainable environment in an increasing number of national courts’ decisions.92
49. As regards its legal content, the right to a clean, healthy and sustainable environment
constitutes an autonomous right.93 The right (i) entails substantive obligations to
ensure protection of clean air, a safe climate, healthy and sustainably produced food,
safe water, adequate sanitation, non-toxic environments in which to live, work and
play, and healthy ecosystems and biodiversity;94 and (ii) entails procedural obligations,
including the right to access environmental information, public participation in
environmental decision-making and access to environmental justice.95
50. Moreover, the right to a clean, healthy and sustainable environment has both a
collective and an individual dimension.
88 William Schabas, The Customary International Law of Human Rights (Oxford University Press, 2021) 333-334, fn. 35.
89 Additional Protocol to the American Convention on Human Rights in the Area of Economic, Social and Cultural Rights : Protocol of San
Salvador (adopted 17 Nov. 1988; entered into force on 16 Nov. 1999), art. 11 (“Everyone shall have the right to live in a healthy environment
and to have access to basic public services.”), see also Advisory Opinion OC-23/17, IACtHR Series A No. 23, 15 November 2017, para. 57;
Arab Charter on Human Rights (2004), art. 38; see also ASEAN Human Rights Declaration, Association of Southeast Asian Nations (ASEAN),
18 November 2012, art. 28(f); and American Declaration on the Rights of Indigenous Peoples, 15 June 2016, AG/RES.2888 (XLVI-O/16),
art. 19(1), see further arts. 19(2)-(4). See also Committee on the Rights of the Child, General Comment No. 26 on children’s rights and the
environment, with a special focus on climate change, CRC/C/GC/26 (22 August 2023), paras. 23, 31, 37, 61, 71.
90 Report of the special Rapporteur on the right to a clean, healthy and sustainable environment, “Good Practices”, A/HRC/43/53, Annex II.
As of December 2019, 156 UN Member States recognized the right in law. Subsequent legal developments in Antigua and Barbuda, Belize,
Canada, Dominica, the Federated States of Micronesia, Grenada, Oman and Saint Lucia increased the total to 164 UN Member States that
recognize the right in law.
91 See Astrid Puentes, ‘Overview of the implementation of the human right to a clean, healthy and sustainable environment’, A/79/270, 2 August
2024; UNEP, “Joint statement of United Nations entities on the right to healthy environment” (UNEP, 8 March 2021); David Boyd, Right
to a healthy environment: good practices, A/HRC/43/53, 30 December 2019., paras. 10-11, see Annex II.
92 See, e.g., Demanda Generaciones Futuras v. Minambiente , Supreme Court of Colombia, STC4360-2018, Decision of 5 April 2018 (Colombia);
Leghari v. Federation of Pakistan, High Court at Lahore, W.P. No. 25501/201, Decision of Apr. 4, 2015 (Pakistan); PSB et al. v. Brazil,
Supreme Court of Brazil, ADPF 708, Decision of 1 July 2022 (Brazil); Held v. Montana CDV-2020-307, Montana First Judicial District
Court, WL 1997864, decision of 14 August 2023. See also NYU Law’s Right to a Healthy Environment (R2HE) Toolkit - UN Environment
Programme, see https://www.r2heinfo.com.
93 Advisory Opinion OC-23/17 (‘The Environment and Human Rights’), IACtHR Series A No. 23, 15 November 2017, para. 62; Walter Brenes
Soto v. Costa Rican Institute of Fisheries and Aquaculture and Others, Supreme Court of Justice (Costa Rica), Resolución No 00912 - 2023,
case 17- 008322-1027-CA, 21 June 2023.
94 David Boyd, Right to a healthy environment: good practices, A/HRC/43/53, 30 December 2019, paras. 8-18. These constitutive elements
have been affirmed by the Committee on the Rights of the Child, General Comment No. 26 on children’s rights and the environment, with a
special focus on climate change, CRC/C/GC/26, 22 August 2023, para. 64.
95 See, in the Inter-American context: Advisory Opinion OC-23/17, IACtHR Series A No. 23, 15 November 2017, paras. 211-241; Convention
on Access to Information, Public Participation in Decision-Making and Access to Justice in Environmental Matters (adopted in Aarhus Denmark
on 25 June 1998 entered into force 30 October 2001), 2161 UNTS 447, art. 1; Regional Agreement on Access to Information, Public
Participation and Justice in Environmental Matters in Latin America and the Caribbean, Escazú, Costa Rica, 4 March 2018, art 1.
18
a. As regards its collective dimension, the right is protective of an essential
quality of the natural environment per se that ‘constitutes a universal value
that is owed to both present and future generations’.96 Thus, the collective
dimension of the right acts in respect of present and future generations and
also extraterritorially.97
b. The right has also an individual dimension, which identifies an intrinsic
relationship with other human rights. 98 A healthy environment is a
prerequisite for the enjoyment and exercise of other rights. Therefore, the right
to a clean, healthy, and sustainable environment, along with any other rights
that cannot be realized or enjoyed without a healthy environment, will be
violated concurrently when a behavior compromises the environment’s
necessary minimum quality.99
51. As regards the intrinsic relationship between the right to a clean, healthy, and
sustainable environment and other rights (such as the right to life, the right to health,
cultural rights, privacy and home rights, various children’s rights, and rights to an
adequate standard of living, including the rights to housing, food, and water), it has
been emphasized by UN Treaty Bodies 100 as well as by regional human rights
courts.101 By way of example, in the case Social and Economic Rights Centre (SERAC)
and Centre for Economic and Social Rights (CESR) v. Nigeria, the African
Commission on Human and Peoples’ Rights, stressed “the importance of a clean and
96 Advisory Opinion OC-23/17 (‘The Environment and Human Rights’), IACtHR Series A No. 23, 15 November 2017, para. 59.
97 See Chiara Sacchi et. al. v. Argentina, Brazil, France, and Germany (Communication Nos. 104-107/2019), CRC/C/88/D/104/2019,
CRC/C/88/D/105/2019, CRC/C/88/D/106/2019, CRC/C/88/D/107/2019, 11 November 2021, paras. 10.5, 10.7; Advisory
Opinion OC-23/17, IACtHR Series A No. 23, 15 November 2017, paras. 101, 103, 104.
98 UNGA, The human right to a clean, healthy and sustainable environment, GA res 76/300, adopted 28 July 2022, A/RES/76/300, para. 2.
See also Advisory Opinion OC-23/17 (‘The Environment and Human Rights’), IACtHR Series A No. 23, 15 November 2017, para. 59.
99 See The human right to a clean, healthy and sustainable environment, Human Rights Council Resolution 48/13, adopted 8 October 2021,
A/HRC/RES/48/13, para. 2; UNGA, The human right to a clean, healthy and sustainable environment, GA res 76/300, adopted 28 July
2022, A/RES/76/300, para. 2. See also AA Cançado Trindade, ‘The Parallel Evolutions of International Human Rights Protection and
Environmental Protection and the Absence of Restrictions upon the Exercise of Recognized Human Rights’ (1991) 13 Revista IIIDH 36, p. 54.
100 In relation to the right to health, see Committee on Economic, Social and Cultural Rights, General Comment No. 14: The right to the highest
attainable standard of health (article 12), 11 August 2000, E/C.12/2000/4, paras 4 and 11; Human Rights Committee, General Comment
No. 36 (Article 6), 3 September 2019, CCPR/C/GC/36, para. 26 and para. 62; Committee on the Rights of the Child, General Comment
No. 26 on children’s rights and the environment, with a special focus on climate change, 22 August 2023, CCPR/C/GC/26, paras 8 and 14.
101 See Advisory Opinion OC-23/17, IACtHR Series A No. 23, 15 November 2017, para. 59; Case of the Indigenous Communities of the Lhaka
Honhat (Our Land) Association v. Argentina, Judgement, IACtHR (ser. C), 6 February 2020, paras. 243-254; Case of Di Sarno v. Italy,
European Court of Human Rights, Judgment, Application No. 30765/08 (2012), para. 110.
19
safe environment that is closely linked to economic and social rights in so far as the
environment affects the quality of life and safety of the individual”.102
52. As affirmed by the UN Special Rapporteur on Human Rights and the Environment,
the “failure of States to take adequate steps to address climate change can constitute
a violation of the right to a healthy environment”.103 States are under the obligations:
(i) to respect the right, namely not to cause or allow significant harm to the climate
system and other parts of the environment, given that such harm impairs the quality
of the environment and climate system required by the right; (ii) to protect the right,
namely to actively protect the climate system and other parts of the environment from
significant harm caused by third parties;104 and (iii) to fulfil the right, namely adopt
and implement laws and policies meant to ensure a minimum level of quality of the
environment (including the climate system).105
53. Furthermore, States have responsibility to indigenous peoples and other traditional
communities who rely on their lands for their material and cultural well-being.106
Therefore, acts and omissions causing significant harm to the climate system also
constitute a grave violation of the right to a clean, healthy, and sustainable
environment, contributing to unprecedented environmental degradation and
associated human rights harms.
54. As is clear from the above, the allegations made by a minority of participants to these
proceedings that the right to a clean, healthy and sustainable environment has not
yet entered the corpus of international law,107 and that there is currently no common
102 African Commission on Human and Peoples’ Rights, SERAC and CESR v. Nigeria, No. 155/96, Decision, 27 October 2001, para. 51.
103 David Boyd, Human Rights Obligations Relating to the Enjoyment of a Safe, Clean, Healthy and Sustainable Environment, 15 July 2019,
A/74/161, see in particular paras. 44; 63. See also The human right to a clean, healthy and sustainable environment, UNGA Resolution
76/300, adopted 28 July 2022, A/RES/76/300.
104 See, with regard to the obligation to protect the right to a healthy environment, Case of the Indigenous Communities of the Lhaka Honhat (Our
Land) Association v. Argentina, Judgement, Inter-American Court of Human Rights (ser. C), 6 February 2020, para. 207
105 David Boyd, Human rights obligations relating to the enjoyment of a safe, clean, healthy and sustainable environment, 15 July 2019, A/74/161,
para. 65. See John H Knox, Framework principles on human rights and the environment (24 January 2018) A/HRC/37/59 annex, paras. 4-6.
106 John H Knox, Framework principles on human rights and the environment (24 January 2018) A/HRC/37/59 annex, para. 41(d); Advisory
Opinion OC-23/17, IACtHR Series A No. 23, 15 November 2017, para. 48.
107 See Verbatim Record CR 2024/34, p. 152 (Germany), paras 29-32; Verbatim Record CR 2024/34, p. 33 (Saudi Arabia), para 13; Verbatim
Record CR 2024/40, p. 47 (USA), para 32; Verbatim Record CR 2024/40, p. 57 (Russia), para 37; Verbatim Record CR 2024/50, p. 69
(Serbia), para 43.
20
understanding of its content and scope,108 are entirely unfounded and should be given
no merit.
55. To conclude, the African Union submits, in line with the position of a majority of the
participants to these proceedings, that the right to a healthy environment is a
historical pillar of the international and, in particular, of the African human rights’
legal framework.
D. THE FOURTH QUESTION
56. The question put by Judge Charlesworth is as follows:
In your understanding, what is the significance of the declarations made by
some States on becoming parties to the UNFCCC and the Paris Agreement
to the effect that no provision in these agreements may be interpreted as
derogating from principles of general international law or any claims or
rights concerning compensation or liability due to the adverse effects of
climate change?
57. An analysis of the terms of the declarations made by several States with respect to
the UNFCCC and the Paris Agreement (the “Declarations”), as well as the context
of the Declarations confirm that the UNFCCC and the Paris Agreement are not –
contrary to what is argued by a minority of States in these proceedings – a “lex
specialis” that would exclude rules of general international law.
58. Rather, the Declarations instead underscore that States are subject to obligations
arising out of principles of general international law (including the duty of prevention)
in addition to the UNFCCC and the Paris Agreement,109 and that they must provide
full reparation for any breach in accordance with the rules of general international
law, including in accordance with the ILC Draft Articles on the Responsibility of
States for Internationally Wrongful Acts (“ARSIWA”).110
108 See Verbatim Record CR 2024/38, p. 17 (Canada), para. 33; Verbatim Record CR 2024/40, p. 47 (USA), para 32; Verbatim Record CR
2024/40, p. 57 (Russia), para 37.
109 WS, paras. 39 et seq.; WC, paras. 17-26; Verbatim CR 2024/44, p. 67 (African Union), para. 18.
110 WC, para. 67; WS, paras. 263-265. See also, e.g., Written Statements of Portugal, paras. 108-115; Tonga, paras. 297-312; IUCN, paras. 546-
575; Singapore, paras. 4.1-4.2; Solomon Islands, paras. 229-233; Kenya, paras. 6.85-6.90; Micronesia, paras. 120-127; Switzerland, paras.
72-73; Saint Vincent and the Grenadines, para. 128; Netherlands, para. 5.3-5.14; France, paras. 179-194; Timor-Leste, paras. 354-357;
India, , paras. 80-88; Samoa, paras. 190-193; Ecuador, paras. 4.2-4.11; USA, paras. 5.1-5.4; Bangladesh, paras. 144-145; Mauritius, paras.
209-210; Antigua and Barbuda, paras. 529-536; El Salvador, paras. 49-52; Brazil, paras. 77-79; Thailand, para. 29; Bahamas, paras. 233-235;
Barbados, , paras. 249-251; Uruguay, paras. 155, 160; DRC, paras. 252-253; Kenya, paras. 6.87-6.90; Albania, para. 132; Marshall Islands,
paras. 55-56.
21
1. Context of the Declarations
59. Between June 1992 and March 1993, five small Pacific Island States, namely, Fiji,
Kiribati, Nauru, Papua New Guinea and Tuvalu, made declarations to the UNFCCC
which were identical in wording, stating that:
“[ratification of the UNFCCC] shall in no way constitute a renunciation of any
rights under international law concerning state responsibility for the adverse
effects of climate change and that no provisions in the convention can be
interpreted as derogating from the principles of general international law”
(emphasis added).111
60. Between April 2016 and March 2017, nine States (Cook Islands, Marshall Islands,
Micronesia, Nauru, Niue, Philippines, Solomon Islands, Tuvalu and Vanuatu) made
separate declarations to the Paris Agreement. Those declarations were broadly
similar in substance while differing slightly in wording from State to State.
61. The Marshall Islands and Vanuatu declared that ratification of the Paris Agreement
shall not constitute a renunciation of any rights under any other laws, including
international law. 112 Similarly, the Cook Islands, Micronesia, Niue, the Solomon
Islands, and Tuvalu stated that ratification shall not constitute renunciation of rights
under international law concerning state responsibility for the adverse effects of
climate change, and that no provision of the Paris Agreement can be interpreted as
derogating from principles of general international law or any claims or rights
concerning compensation.113
62. Despite some differences in language, the declarations under both the UNFCCC and
the Paris Agreement substantively have the same meaning as well as the same object
and purpose: that is, to clarify that the UNFCCC and the Paris Agreement do not
111 Declarations of Fiji, Kiribati, Nauru, Papua New Guinea, and Tuvalu, accessible here; Daniel Bodansky, Jutta Brunée and Lavanya Rajamani,
International Climate Change Law (OUP 2017), p. 158.
112 Declarations of the Marshall Islands and Vanuatu, accessible here.
113 Declarations of the Cook Islands, Micronesia, Niue, Solomon Islands, and Tuvalu, accessible here. The Declaration of Nauru, accessible here,
states that: “[…] the ratification of the Agreement shall in no way constitute a renunciation of any rights under international law concerning
State responsibility [for] the adverse effects of climate change […] no provisions in the Agreement can be interpreted as derogating from the
principles of general international law […] Article 8 and decision 1/CP.21, paragraph 51 in no way limits the ability of Parties to UNFCCC
or the Agreement to raise, discuss, or address any present or future concerns regarding the issues of liability and compensation.” The Declaration
of the Philippines, accessible here, states that “[…] its accession to and the implementation of the Paris Agreement shall in no way constitute a
renunciation of rights under any local and international laws or treaties, including those concerning State responsibility for loss and damage
associated with the adverse effects of climate change […]”.
22
prejudice existing remedial rights, thereby ensuring recourse to remedies under
general international law principles separately and in addition to those available
under article 4(4) of the UNFCCC.114
63. This is further confirmed by the contextual history of the declarations to the UNFCCC.
64. The intention of the UNFCCC was to provide a framework convention on climate
change that “represented not an end point, but rather a punctuation mark in an
ongoing process of negotiation that continues to this day.”115 In recognition of the need
to build on the framework it provided, the UNFCCC was therefore designed to be
supplemented by general international law, not to condition it.
65. Of particular note, the travaux préparatoires in the final stages of negotiations of the
UNFCCC show that the Intergovernmental Negotiating Committee considered
including operative clauses that expressly conferred on signatory States the obligation
to respect the general international law principles of State responsibility and the
principle of prevention.116 When the suggested provisions were removed from the final
version of the UNFCCC, several specially-affected States added language in their
declarations to confirm that general rules of international including the law on State
responsibility still applied.
66. That similar declarations were made in relation to the Paris Agreement, and that no
States ever expressed any objections to these declarations as explained infra,
demonstrates a continuation of the intention for the climate regime’s treaty
obligations to work in tandem with general international law norms.
67. In contrast, the Court will note that no express provision was ever contemplated and
in fact included in the text of either the UNFCCC or the Paris Agreement suggesting
that the Parties intended to derogate to general international law principles. As
emphasised by Burkina Faso in its submissions:
[…] aucun de[s] participants n’a apporté la preuve d’une dérogation expresse
à toutes ces règles du droit international. Aucun n’a apporté la preuve d’une
114 UNFCCC, Article 4(4): “The developed country Parties and other developed Parties included in Annex II shall also assist the developing country
Parties that are particularly vulnerable to the adverse effects of climate change in meeting costs of adaptation to those adverse effects.” See Daniel
Bodansky, ‘The United Nations Framework Convention on Climate Change: a Commentary’ (1993) Yale Journal of International Law, p. 529.
115 Daniel Bodansky and Lavanya Rajamani, ‘Evolution and Governance Architecture of the Climate Change Regime’, in Detlef Sprinz and Urs
Luterbacher (eds.), International Relations and Global Climate Change: New Perspectives (MIT Press, 2nd edn, 2016).
116 Intergovernmental Negotiating Committee for a Framework Convention on Climate Change, Consolidated Text Based on Proposals Regarding
Principles and Commitments, Presented by Delegations, 27 August 1991, II Principles, pp. 4 and 7.
23
dérogation implicite à ces règles, comme cela est requis par le droit
international […].117
“[…] aucun des participants qui soutient la doctrine de la lex specialis n’a
invoqué une disposition de la Convention-cadre des Nations Unies sur les
changements climatiques, du Protocole de Kyoto ou de l’Accord de Paris qui
exclurait les autres obligations applicables aux émissions anthropiques de
gaz à effet de serre, notamment celles relatives aux droits humains, y inclus
les droits des peuples, le droit de la mer et le droit de l’environnement. Ceci
est bien compréhensible puisque l’Accord de Paris, au lieu de déroger à ces
obligations, réaffirme au contraire leur application aux mesures prises pour
faire face aux changements climatiques”.118
2. Significance of the Declarations
68. According to the UN’s Guide to Practice on Reservations to Treaties:
[an interpretive declaration] does not modify treaty obligations. It may only
specify or clarify the meaning or scope which its author attributes to a treaty
or to certain provisions thereof and may, as appropriate, constitute an
element to be taken into account in interpreting the treaty in accordance with
the general rule of interpretation of treaties […].119
69. It is also generally accepted that approval of, or opposition to, the interpretive
declaration by other contracting parties to a treaty shall be taken into account in its
interpretation.120
70. In light of the above, the African Union submits that the Declarations which
essentially clarify that general principles of international law, including rules on state
responsibility, apply in addition to the UNFCCC and the Paris Agreement, should be
given significant weight by the Court in responding to Questions 1 and 2 of the UNGA
Resolution, particularly as they have not been contested by any other States. Rather,
the Declarations have in fact been generally accepted by other States.121
71. Indeed, the Court will note that no State has ever submitted any interpretative
declaration contradicting the terms of the State Declarations, which have been made
117 Verbatim CR 2024/37, p. 43 (Burkina Faso), para. 3. (emphasis added)
118 Written Comments of Burkina Faso, para. 27. (emphasis added)
119 Alain Pellet, Guide to Practice on Reservations to Treaties, Sixty-third Session [2011] vol II part II UNYBILC, Guideline 4.7.1.
120 Ibid., Guidelines 4.7.2 and 3.6.
121 The position in this regard is that the silence of States, understood as the absence of protest, has legal consequences, through the concepts of
acquiescence or tacit consent of States to a factual or legal situation that affects or might affect their rights. See J. Miller and T. Cottier,
“Acquiescence” in R Bernhardt (ed), Encyclopedia of Public International Law (vol 7, 1984) 5; E Suy, Les actes juridiques unilateraux en droit
international public (1962) 66; M E Villiger, Customary International Law and Treaties (1985) 19.
24
throughout the evolution of the international law climate regime, starting with the
first international agreement (UNFCCC) in 1994, followed by the Kyoto Protocol in
1997122 and, finally, the Paris Agreement in 2015. This demonstrates a consistent
acceptance of, and support for, these declarations.
72. Indeed, a number of parties to these proceedings (including but not limited to some of
those who made the Declarations), which are also signatories to the UNFCCC and
Paris Agreement, have instead expressly confirmed their agreement with the
Declarations.123
73. On the basis of the significant support for these Declarations, both historically and in
the present proceedings, the Court should therefore interpret the UNFCCC and Paris
Agreement in light of the contents of the Declarations that, importantly, were made
by specially-affected States.124
74. Contrary to the position of a minority of States in these proceedings, arguing that the
UNFCCC and the Paris Agreement constitute a “lex specialis”, the Declarations
reinforce the interpretation that the UNFCCC and Paris Agreement should be
supplemented by general principles of international law (including inter alia, the
principle of prevention, and the general international law principles on State
responsibility).
75. As underlined by Professor Mayer:
“the special rules on climate change contained in the UNFCCC and other
regimes do not derogate from general international law.”125
76. Remedial measures are therefore, similarly not limited to those provided under the
UNFCCC and Paris Agreement, namely the creation of specialized funds and
compliance mechanisms.
122 The following States made interpretive declarations (accessible here) upon ratification of the Kyoto Protocol: Cook Islands, Niue, Kiribati.
123 See, for example, the Written Statements of Belize, p. 19, fn 113-115; Burkina Faso, p. 66, para. 119. See also the Written Comments of
Barbados, para. 34; Kenya, para. 4.6, fn. 199; Nauru, paras. 27-31, and Vanuatu, para. 156. Likewise, the Verbatim records CR 2024/46, p.
8 (Nauru), paras. 2, 7, 16, and fns. 4-5; Verbatim CR 2024/45, p. 48 (Namibia), paras. 54-55; Verbatim CR 2024/41, p. 34 (Ghana), para.
11; Verbatim CR 2024/49 pp. 50-51 (Seychelles), para. 7; Verbatim CR 2024/43, p. 49 (Kiribati), para. 33 and fn. 75; Verbatim CR
2024/36 p. 82 (Barbados), para. 7; Verbatim CR 2024/37, pp. 10-11 (Belize), para. 5; Verbatim CR 2024/39, p. 63 (Egypt), para. 27.
124 The African Union refers to its position in Legal Consequences of the Separation of the Chagos Archipelago from Mauritius in 1965, where it
emphasised that :“[a]s the Court has underlined in the North Sea Continental Shelf Cases, the practice that is essential to look at when dealing
with an issue of international law is the practice of the ‘concerned states’. Written Comments of the African Union in Legal Consequences of
the Separation of the Chagos Archipelago from Mauritius in 1965, para. 23.
125 B. Mayer, The International Law on Climate Change (CUP 2021), p. 86.
25
77. Rather, States found to be responsible for harmful conduct are required to provide full
reparation in accordance with the law on State responsibility, notably cessation and
non-repetition (Article 30 ARSIWA), restitution (Article 35 ARSIWA), compensation
(Article 36 ARSIWA) and satisfaction (Article 37 ARSIWA).
78. In sum, the Declarations made by some States on becoming parties to the UNFCCC
and the Paris Agreement confirm that in addition to the UNFCCC and the Paris
Agreement, States are subject to obligations arising out of principles of general
international law (including the duty of prevention) and must provide full reparation
for any breach in accordance with the rules of general international law, including in
accordance with ARISWA. This is not only the position of the African Union,126 but
also the position of the majority of participants to these proceedings.127
Hajer Gueldich
Legal Counsel
Office of the Legal Counsel, African Union Commission
Addis Ababa, Ethiopia
126 WS, para. 80, as well as WC, paras. 42 et seq.: “The Court must take into account the whole corpus of international law”.
127 See e.g., Written Statements of Vanuatu, paras. 222 et seq.; Barbados, para. 197; Egypt, para. 74; Kenya, para. 5.51; Sierra Leone, paras. 3.1
and 3.125; Mauritius, para. 123. See also Written Comments of Ghana, paras. 3.16-3.20; Mauritius, paras. 87-90. Likewise, the Verbatim
records CR 2024/51, p. 64 (Comoros), para. 4; Verbatim CR 2024/50, p. 38 (Sri Lanka), para. 7; Verbatim CR 2024/52, p. 19 (Viet
Nam), para. 8; Verbatim CR 2024/44, p. 12 (Latvia), para. 3; Verbatim CR 2024/49, p. 60 (The Gambia), para. 6; Verbatim CR 2024/36,
p. 69 (Bangladesh), para. 10; Verbatim CR 2024/37, p. 22 (Bolivia), para. 14; Verbatim CR 2024/39, p. 49 (Nordic Countries), para. 29;
Verbatim CR 2024/39, p. 59 (Egypt), para. 13; Verbatim CR 2024/41, p. 21 (Sierra Leone), para. 7; Verbatim CR 2024/46, p. 32 (Pacific
Islands Forum), para. 11; Verbatim CR 2024/46, p. 35 (New Zealand), para. 19; Verbatim CR 2024/48, p. 64 (Saint Lucia), para. 13.