The International Court of Justice (ICJ) delivered a pivotal ruling in July 2025, asserting that all nations are bound by international law to address the climate crisis, which it deemed an urgent existential threat. This ruling builds on previous climate litigation and reinforces the legal duty to prevent environmental harm, regardless of treaty participation. As world leaders convene for Cop30 in Brazil, the ICJ's decision is anticipated to shape negotiations, particularly concerning fossil fuel policies and the responsibilities of industrialized nations. Experts are calling for compliance with the ruling and for fossil fuel lobbyists to be banned from negotiations, highlighting the need for transparency and accountability in climate action.