Trump has reportedly decided to withdraw from the Paris climate deal

President Donald Trump has decided to take the US out of the Paris climate accord, Jonathan Swan of the news website Axios first reported Wednesday, citing two sources.

Politico and CNN are also reporting that Trump intends to pull out of the agreement, citing White House officials. A White House representative didn't immediately respond to a request for comment.

Whether Trump will stay in the deal — a cornerstone of President Barack Obama's environmental legacy — has been a looming question of his nascent presidency. On his recent trip abroad, Trump was pressured by European allies to stay a part of the accord.

Trump tweeted Wednesday morning that he would announce his decision "over the next few days."

The US Environmental Protection Agency's administrator, Scott Pruitt, who has repeatedly called for the US to exit the agreement, is part of a small team figuring out the details of a withdrawal, according to Axios.

Trump has previously called climate change a "hoax" and said while campaigning that he would "cancel" the Paris deal if elected.

The Paris agreement, reached in December 2015, was a landmark moment in the environmental movement. It marked the first time that nearly every country, including all of the world's biggest polluters, came together to limit carbon emissions. The pact was designed to keep the planet from warming by more than 1.5Â degrees Celsius above preindustrial levels.

Climate experts warn that an increase of more than 2 degrees Celsius could bring irreversible consequences, from a rise in sea level to unpredictable shifts in weather and drought. That could devastate agriculture and affect life on the coasts, where the vast majority of people live.

Amid today’s emissions levels, the average global surface temperature is increasing at a rate of about 0.1 degrees Celsius a decade.

Some scientists already think the world has emitted too much carbon to keep the world below the 2-degree goal but have advised that the sooner countries act, the better humanity will fare in the long run.

Two-thirds of Americans said they supported signing on to an agreement that would legally bind the US and the rest of the world to cut carbon emissions, according to a New York Times/CBS News poll released before talks began in Paris.

Major companies supported the agreement as well. Apple, BP, Google, Microsoft, Shell, and several other companies sent Trump a letter in April encouraging him to keep the US in the pact because they believe it strengthens their competitiveness, creates jobs, and reduces business risk.

The official United Nations account tweeted shortly after news broke of Trump's apparent intention to withdraw on Wednesday morning that "Climate change is undeniable" and "Climate action is unstoppable."

Climate solutions provide opportunities that are unmatchable.

-@antonioguterres https://t.co/a8O14NCLUc — United Nations (@UN) May 31, 2017

The Paris agreement, also known as COP21, was the plan to reverse the gloom-and-doom trajectory that scientists warned the planet was on. It laid out a framework for countries to adopt clean energy and phase out fossil fuels. Each country submitted its own climate-action plan laying out how it would achieve these goals.

It wasn't legally binding to the US, because Congress never formally agreed to adopt the treaty. But the Obama administration used its power to enact as many carbon-cutting measures as possible to position the US as a leader in fighting climate change.

The US is the world's second-largest carbon emitter after China. This was the first climate accord that both superpowers agreed to, which legal experts heralded as the best sign of its success worldwide.

The US Congress never ratified the Kyoto Protocol in 1992, essentially making the entire global agreement moot.

Trump's planned exit could lead to a tailspin of other countries exiting the Paris agreement.