President Biden signed an executive order this afternoon, in one of his first acts upon taking office, returning the United States to the Paris Agreement. The move fulfills a promise he made immediately after the November election, and reverses one of Donald Trump’s most controversial actions as President.

The Paris Agreement is a multi-nation pact developed by parties to the United Nations Framework Convention on Climate Change (UNFCCC) to combat climate change. The agreement’s main goal is to limit the global temperature increase in this century to below 2 degrees Celsius above pre-industrial levels, and to work toward limiting the increase to 1.5 degrees.

The Trump administration announced in June 2017 that it intended to withdraw from the agreement, claiming the economic cost of the accord was too high, and unfair to the United States. The withdrawal became effective in November 2020. 189 nations have ratified the agreement, and the U.S. is the only country to have formally exited.

Biden has clearly signalled his intention to place the US in the center of the fight against climate change. Biden has set climate policy as one of his administration’s top priorities, and has made key appointments including Former Secretary of State John Kerry as Special Presidential Envoy for Climate – the first time the NSC will include an official dedicated to climate change – and sustainable investing veteran and Paris Agreement negotiator Brian Deese as Director of the National Economic Council.