IUCN welcomes UN General Assembly affirmation of States’ obligations to protect the climate system
On Wednesday 20 May the United Nations General Assembly (UNGA) adopted a landmark resolution backing the findings of the International Court of Justice (ICJ) in its July 2025 Advisory Opinion on State Obligations on Climate Change. With 141 votes in favour, 28 abstentions and 8 against, the international community has voted overwhelmingly in favour of an Opinion that has clarified that States have obligations under international law to protect the climate system and that there are legal consequences under international law, should such obligations be breached.
The UNGA Resolution itself calls for States to comply with their respective obligations, which can be found both in treaty law (not only the Paris Agreement) and in customary international law. You can find the full text of the resolution here.
In the resolution, the General Assembly also expressed its determination to translate the Court’s findings into enhanced multilateral cooperation and accelerated climate action at all levels, consistent with international law.
The resolution concludes by requesting the Secretary General to submit
“a report containing ways to advance compliance with all obligations in relation to the Court’s findings, taking into account the best available science and possible gaps in multilateral efforts to address the adverse effects of climate change in accordance with international law, without prejudice to the legal positions of States and without implying any determination of responsibility, while ensuring coordination, coherence and complementarity with existing mechanisms and procedures, including under the United Nations Framework Convention on Climate Change and the Paris Agreement. (para 10)”
IUCN participated in the historical proceedings that led to the ICJ Advisory Opinion with two set of written statements and engagement in the oral proceedings through the Chair of its World Commission on Environmental Law (WCEL), Prof Christina Voigt, Director General, Dr Grethel Aguilar and WCEL Climate Change Law Specialist Group Co-chair, Prof Francesco Sindico. IUCN is pleased to see the core points it put forward to the Court included in the UNGA Resolution.
At the 2025 IUCN World Conservation Congress in Abu Dhabi, the Union also adopted Resolution 8.138 welcoming the ICJ Advisory Opinion on Climate Change, which ‘urges all IUCN Members to take all appropriate measures to respect and implement the obligations set out in the Advisory Opinion’. The same resolution also mandates the preparation of a study of relevant legal instruments and approaches across all levels to support the implementation of the Court's findings. IUCN and WCEL therefore look forward to collaborating with the UN system in this endeavour.
IUCN Director General, Dr Grethel Aguilar, commenting on the adoption of the UNGA Resolution on 20 May, said: “Climate change is not a distant threat – it is an existential crisis for humanity and the natural world that we rely on. IUCN is honoured to have contributed to the proceedings that informed the ICJ Advisory Opinion, and we warmly welcome its affirmation by the UN General Assembly. This is a powerful reminder that protecting the climate system is not only an environmental imperative, but a legal and moral responsibility. We urge all countries to act with the urgency, ambition and solidarity that this moment demands, and to uphold their obligations under international law without further delay. The time to address global warming, with true resolve, is now.”
Prof Christina Voigt, IUCN WCEL Chair celebrated the UNGA Resolution: “The backing of the ICJ's findings by a supermajority of UN members provides proof of a world-wide consensus on the legal obligations of states on climate change. This alignment of law and politics, the support of multilateralism and the turn to implementation give hope, direction and the legal architecture for getting there. Profound respect and thanks to the Government of Vanuatu, the core group and its many allies, and to the Pacific Island Students Fighting Climate Change and the World Youth for Climate Justice for their leadership.”
Prof Francesco Sindico, IUCN WCEL Climate Change Law Specialist Group commented: “The WCEL Climate Change Law Specialist Group welcomes the UNGA resolution and looks forward to implementing the Abu Dhabi resolution. Just like in the proceedings that led to the ICJ AO, IUCN is uniquely positioned to provide a science informed legally robust analysis of how States can implement the ICJ Advisory Opinion.”