The United States officially rejoined the Paris climate agreement on Friday.

The US State Department said in a statement on Friday that President Joe Biden signed the instrument to bring the United States back into the Paris Agreement on January 20. 

Nearly 200 countries across the world have adopted the Paris pact, the landmark international accord to limit global warming and reduce greenhouse gas emissions.

Today, the United States 🇺🇸 re-joined the #ParisAgreement – the international response to the climate crisis.

But what exactly is the Paris Agreement? And how does it work? pic.twitter.com/JOnm9s7iRf

— UN Climate Change (@UNFCCC) February 19, 2021

According to the US State Department, the Paris Agreement’s purpose is “both simple and expansive: to help us all avoid catastrophic planetary warming and to build resilience around the world to the impacts from climate change we already see.”

“Now, as momentous as our joining the Agreement was in 2016 — and as momentous as our rejoining is today — what we do in the coming weeks, months, and years is even more important,” the statement said.

“Climate change and science diplomacy can never again be “add-ons” in our foreign policy discussions. Addressing the real threats from climate change and listening to our scientists is at the center of our domestic and foreign policy priorities,” the statement read. 

“It is vital in our discussions of national security, migration, international health efforts, and in our economic diplomacy and trade talks.”

“We are reengaging the world on all fronts, including at the President’s April 22nd Leaders’ Climate Summit. And further out, we very much looking forward to working with the United Kingdom and other nations around the world to make COP26 a success,” the statement concluded.

Former US President Donald Trump in 2017 announced his intention to withdraw the US from the treaty and officially notified the United Nations in 2019.

The US officially left the agreement on November 4, 2020.