The UN's top court on Wednesday ruled climate change an "existential problem of planetary proportions" and said countries had a legal duty to act or face consequences.

The ICJ issued an opinion on climate change that stated the obligations of the Paris Agreement come with legal liability. A concern raised by Trump as early as 2017.

In a landmark decision, the International Court of Justice found that polluting countries are now legally obligated to address global warming. In a unanimous ruling by a panel of 15 judges, the court said high-emitting countries do have legal obligations under international law to address the “urgent and existential threat” of climate change.