International Court of Justice to Issue Advisory Opinion on Climate Change

On July 23, 2025, the International Court of Justice (ICJ) is set to deliver a pivotal advisory opinion on the legal obligations of states concerning climate change. This follows a request from the United Nations General Assembly (UNGA) in March 2023, initiated by Vanuatu and other small island developing states, seeking clarification on nations' responsibilities to protect the climate system and the legal consequences of failing to meet these obligations.

The ICJ's forthcoming opinion, though nonbinding, carries significant legal and political weight. It is anticipated to influence international law development, shape national policies, and guide future climate-related litigation worldwide. The proceedings have seen unprecedented global participation, reflecting the urgency and importance of addressing climate change through legal frameworks.

Background and Context

In March 2023, the UNGA adopted a resolution requesting the ICJ to provide an advisory opinion on the obligations of states regarding climate change. This initiative was spearheaded by Vanuatu, a Pacific island nation acutely vulnerable to the impacts of climate change, including rising sea levels and extreme weather events. The resolution aimed to clarify the legal responsibilities of nations in mitigating climate change and to outline the consequences of failing to meet these obligations.

UN Secretary-General António Guterres supported the resolution, stating, "Advisory opinions can provide much-needed clarification on existing international legal obligations." He emphasized that such opinions could assist the UN and member states in taking "the bolder and stronger climate action that our world so desperately needs."

Proceedings and Participation

The ICJ's proceedings have witnessed unprecedented global engagement. From December 2 to 13, 2024, the court held hearings where 96 states and 11 international organizations presented oral arguments. Developed nations generally advocated for interpreting responsibilities based on existing nonbinding treaties like the Paris Agreement. In contrast, developing countries and small island states pushed for firmer emission reductions and financial support from high-emission countries.

Vanuatu's representative for climate change, Ralph Regenvanu, highlighted the significance of the proceedings, stating, "The outcome of these proceedings will reverberate across generations, determining the fate of nations like mine and the future of our planet."

Significance of the Advisory Opinion

Although the ICJ's advisory opinions are not legally binding, they carry substantial legal and political weight. Such opinions can influence international law development, shape national policies, and guide future litigation. They are often cited by domestic courts and international tribunals, potentially setting new standards for state and corporate conduct.

The forthcoming advisory opinion is expected to influence climate-related litigation and policy-making worldwide. It may embolden claimants in domestic and international courts, increasing the risk of climate-related litigation against both states and corporations. Additionally, the opinion could reinforce and build upon recent international legal trends that place greater emphasis on both state and corporate responsibility for climate change.

Implications for Small Island Developing States

For nations like Vanuatu, the advisory opinion holds particular significance. These countries are disproportionately vulnerable to climate change impacts, including rising sea levels and extreme weather events. The ICJ's opinion could provide a moral imperative and legal framework to hold major greenhouse gas-emitting countries accountable for damages to vulnerable nations.

Vanuatu's Prime Minister, Alatoi Ishmael Kalsakau, emphasized the urgency of the situation, stating, "Ambition towards achieving the 1.5-degree target is still far from what is needed." He expressed hope that the ICJ's advisory opinion could provide clarity that would benefit global efforts to address the climate crisis and further boost cooperation.

Potential Impact on Climate Litigation and Policy

The forthcoming advisory opinion is expected to influence climate-related litigation and policy-making worldwide. It may embolden claimants in domestic and international courts, increasing the risk of climate-related litigation against both states and corporations. Additionally, the opinion could reinforce and build upon recent international legal trends that place greater emphasis on both state and corporate responsibility for climate change.

UN High Commissioner for Human Rights, Volker Türk, welcomed the resolution, stating that an ICJ advisory opinion "could be an important catalyst for the urgent, ambitious, and equitable climate action that is needed to stop global heating and to limit and remediate climate-induced human rights harms."

Historical Context and Precedents

This initiative follows a similar request made by the Marshall Islands and Palau in 2011, which did not advance. The current case is driven by alarming new climate and emissions trends, along with recent warnings from the UN Intergovernmental Panel on Climate Change. The ICJ's forthcoming opinion is anticipated to serve as the most authoritative statement on climate change and human rights in international law to date.

The ICJ's advisory opinion on July 23, 2025, represents a significant moment in the global effort to address climate change through legal mechanisms. While nonbinding, the opinion is expected to influence international law, national policies, and climate-related litigation, potentially setting new standards for state and corporate conduct in mitigating climate change.