Why in news?
On 23 July 2025 the International Court of Justice (ICJ) issued an advisory opinion in response to a request led by Vanuatu and other small island states. The court clarified nations’ legal duties to address climate change and the consequences of failing to act.
Background
Vanuatu and a coalition of Pacific island nations approached the ICJ in 2023, arguing that rising sea levels threaten their existence and that existing climate treaties alone cannot safeguard their rights. They sought clarification on how customary international law, human rights conventions and environmental treaties intersect when states fail to curb greenhouse‑gas emissions.
Highlights of the opinion
- Climate change as a human rights issue: The court recognised that climate change poses an existential threat and impairs fundamental rights such as life, health, housing and culture. A clean, healthy and sustainable environment was affirmed as a universal human right.
- Clear legal obligations: States must prevent, reduce and control greenhouse‑gas emissions in line with the best available science. The opinion uses 1.5 °C above pre‑industrial temperatures as the benchmark that states should not exceed.
- General law applies alongside treaties: The court rejected arguments that climate treaties (like the UNFCCC or Paris Agreement) provide the only legal yardstick. It held that customary international law and human rights obligations also bind states; therefore failure to act constitutes a wrongful act.
- Duties to support vulnerable countries: Developed states are asked to provide financial and technological assistance to countries most affected by climate change, recognising principles of equity and common but differentiated responsibilities.
- Protection of statehood: The court noted that the disappearance of territory due to sea‑level rise does not automatically extinguish statehood of island nations. They remain entitled to their maritime zones and international recognition.
Implications
Although advisory opinions are non‑binding, they influence international negotiations and domestic litigation. The ruling strengthens the legal case for climate‑vulnerable countries seeking reparations and could shape future court cases. It also puts moral and legal pressure on major emitters to accelerate emission cuts and support adaptation efforts in developing countries.