The International Court of Justice (ICJ) issued a groundbreaking advisory opinion on July 23, 2025, declaring that states are legally obligated to combat climate change. Failing to take adequate action could breach international law and potentially trigger legal consequences, including reparations.

Though non-binding, the unanimous ruling carries substantial political and legal weight. It characterizes a clean, healthy environment as a fundamental human right, a first for the Court. The decision clarifies that obligations under the Paris Agreement and broader environmental and human rights laws require states to curb emissions, cooperate globally, and support vulnerable nations.

The advisory opinion was prompted by a UN General Assembly request spearheaded by Vanuatu and supported by over 130 nations concerned about existential threats to small island states. UN court emphasized that wealthy countries must assist developing countries with adaptation and may be held accountable for harms caused by excessive emissions.

Experts anticipate the ICJ opinion will strengthen global climate litigation, empower vulnerable nations seeking compensation, and influence negotiations at COP30. While states must still prove causation, the ruling marks a crucial legal breakthrough for climate justice.