The United States is officially back in the Paris climate accord. Exactly one month after Joe Biden took office the world’s largest economy and second-largest carbon emitter was formally back in the 2015 accord aimed at confronting the planet’s dangerously rising temperatures.

The re-entry of the United States means that the Paris accord again includes virtually every country after Biden’s predecessor Donald Trump made the United States the sole outlier.

“Climate change and science diplomacy can never again be ‘add-ons’ in our foreign policy discussions,” Secretary of State Antony Blinken said in a statement saluting the return of the United States.

“Addressing the real threats from climate change and listening to our scientists is at the centre of our domestic and foreign policy priorities. It is vital in our discussions of national security, migration international health efforts, and in our economic diplomacy and trade talks.”

The Paris accord aims to limit global temperature rises to two degrees Celsius (3.6 Fahrenheit) above pre-industrial levels and to pursue efforts to go down to 1.5 degrees.

Trump, an ally of the fossil fuel industry, had argued that the Paris climate accord was unfair to the United States.