A landmark decision by a top UN court has cleared the way for countries to sue each other over climate change, including over historic emissions of planet-warming gases. But the judge at the , UN's Top Court Says All Countries Have to Act Against Climate Change. Here Are the Key Takeaways THE HAGUE, Netherlands (AP) — The United Nations' top court has issued a landmark advisory , Countries must address climate change threat, U.N.'s highest court says The opinion by the International Court of Justice, also known as the World Court, was immediately welcomed by environmental , The International Court of Justice (ICJ) in The Hague, Netherlands, issued its advisory opinion on the obligations of States in respect of climate change, read out by the President of the Court, Judge Iwasawa Yuji, on Wednesday., The UN's top court has just said in a landmark climate opinion that a "clean, healthy and sustainable environment" is a human right and, if countries fail to take "appropriate action to protect , .