The United Nations’ top court says countries failing to implement measures to mitigate climate change may be in violation of international law, opening the door for nations harmed by its effects to seek reparations.

International Court of Justice determines countries are responsible for corporate emissions and must cooperate to achieve concrete emission reduction targets.

For nearly a decade, U.N. Secretary-General Antonio Guterres has been using science to warn about ever more dangerous climate change in increasingly urgent tones. In an exclusive interview with The Associated Press,

A decade since the Paris Agreement was signed in 2015, two big outstanding questions have delayed action: Who is responsible for climate change and who should pay?

The top UN court opens a hearing to deliver a landmark advisory opinion on climate change.