UN adopts landmark resolution to clarify States' legal obligations with respect to climate change

On 29 March 2023, the Pacific nation of Vanuatu (Vanuatu) successfully spearheaded a resolution which, following adoption by consensus by the UN General Assembly, has been hailed a “win for climate justice of epic proportions” by Vanuatu's Prime Minister.

The landmark resolution calls on the International Court of Justice (the ICJ) – the UN’s principal judicial organ – to provide an advisory opinion on the legal obligations of States with respect to climate change. It also seeks advice on the legal consequences when States’ actions or omissions cause significant climate harm to others, particularly vulnerable island nations and future generations.

Background of the resolution 

Like other Pacific Island nations, Vanuatu considers that it bears little responsibility for the climate crisis but is acutely vulnerable to its impacts, including rising sea levels, which threaten its very existence.

In 2021, Vanuatu announced its intention to seek an advisory opinion from the ICJ, following a campaign launched in 2019 by a group of students from a university in nearby Fiji. Since then, Vanuatu built a core group of 18 countries to join its bid. By the time of adoption, the cross-regional core group secured more than 130 States as co-sponsors of the resolution.

The ICJ advisory opinion marks the next step in Vanuatu’s (and other Pacific Island nations’) legal strategy around the impact of climate change. Along with the ICJ advisory opinion, Vanuatu, as part of the Commission of Small Island States, has also sought an advisory opinion from the International Tribunal on the Law of the Seas (ITLOS). The ITLOS is considering what specific obligations the UN Convention on the Law of the Seas (UNCLOS) places on parties to: i) prevent or reduce the effects of climate change (including rising sea levels); and ii) protect the marine environment in relation to climate change impacts.

What the resolution calls for

As per the UN resolution, the questions which will be put before the ICJ are:

• What are the obligations of States under international law to ensure the protection of the climate system and other parts of the environment from anthropogenic emissions of greenhouse gases for States and for present and future generations;
• What are the legal consequences under these obligations for States where they, by their acts and omissions, have caused significant harm to the climate system and other parts of the environment, with respect to:
  • States, including, in particular, small island developing States, which due to their geographical circumstances and level of development, are injured or specially affected by or are particularly vulnerable to the adverse effects of climate change?
  • Peoples and individuals of the present and future generations affected by the adverse effects of climate change?

Next steps

The UN will communicate the resolution to the ICJ in the coming weeks and the ICJ will then organise written and oral proceedings over the next few months. As part of the process, UN Member States will be able to submit written statements, comment on statements submitted by other States, and make oral statements during public proceedings.

The advisory opinion is expected to be issued within the next 18 months.

Possible implications

Legally binding instruments, adopted at international and EU levels, already impose climate change obligations on States. Under the Paris Agreement, the first-ever universal global climate change agreement ratified by 195 States and the EU at the 2015 UN Climate Change Conference (COP21), States agreed to aim to limit global warming to 1.5 C° with an upper limit of 2 C°. It is a binding agreement, which has supported climate change decisions rendered against States in a number of jurisdictions, but many of its articles do not imply specific obligations or are there primarily to facilitate international collaboration.

At EU level, the 2021 European Climate Law enshrined into law the EU’s goal to become climate-neutral by 2050. The law also sets the intermediate target of reducing net greenhouse gas emissions by at least 55% by 2030, compared to 1990 levels.

The advisory opinion could, if the ECJ considers that States have stronger and/or more precise obligations than those contained in these instruments, increase the risk of climate change litigation. Whilst ICJ advisory opinions are non-binding, they can indeed carry legal authority and moral weight and can ultimately become part of customary international law, which is legally binding on States. As UN Secretary General Antonio Guterres commented, they can have “tremendous importance and can have a long-standing impact on the international legal order”.

The upcoming advisory opinion could influence court proceedings directed against States or public entities before domestic or regional courts (such as the European Court of Human Rights, where several landmark climate change litigation cases against certain Member States of the Council of Europe are ongoing). In turn, victorious cases against States may influence climate change proceedings against corporations, as illustrated by the landmark Shell judgment rendered by the Hague District Court in 2021.

Small island nations, and Vanuatu in particular, have realised the impact of having a strong and consistent legal strategy. If there are consistent judgments on the issues in various international tribunals (including the ICJ and ITLOS) there would be strong arguments in favour of the development of customary international law around climate change. These advisory opinions are likely to shape the discourse around climate change and accountability for polluting states in the years to come.