European Council President Donald Tusk has appealed directly to US President Donald Trump not to pull the United States out of the Paris Agreement on climate change.

The President is due to announce his position on the Paris Accord this evening, with sources indicating to several media outlets that the country will be withdrawing from the agreement.

Tusk, urged Mr Trump to change his mind, tweeting: "Please don't change the (political) climate for the worse."

.@realDonaldTrump please don't change the (political) climate for the worse.

— Donald Tusk (@eucopresident) June 1, 2017

The European Union (EU) and China previously announced they were standing together to push forward implementation of the accord, an unusual alliance that emphasises the absence of the US from the playing field.

"The EU and China are joining forces to forge ahead on the implementation of the Paris Agreement and accelerate the global transition to clean energy," EU Commissioner on Climate Action and Energy Miguel Arias Cañete told US media.

What is the Paris Agreement?

The Paris deal, which was brokered by Barack Obama in 2015, commits nations to curbing carbon emissions. It was the first legally binding global deal to fight climate change.

Under the deal, Mr Obama committed the US to cutting its emissions by between 26% and 28% from 2005 levels by 2025.

But Mr Trump, who has called climate change a hoax, made pulling out of the deal a key pledge of his presidential campaign, saying it weakens the US economy.

Instead, he has vowed to boost America's coal and oil industries.

His aides are said to be split over the issue, with his daughter and White House adviser Ivanka Trump reportedly against a withdrawal.

And the President has come under pressure from business leaders and international allies to keep America in the deal.

Tesla's Elon Musk threatened to quit White House advisory councils if the President pulls out.

A withdrawal would leave the US in the company of Syria and Nicaragua as the world's only non-participants in the 195-nation accord.

It would also deepen a rift with US allies in Europe and elsewhere.

Leaders at a G7 summit this month expressed frustration at the US stance over the issue.

"The entire discussion about climate was very difficult, if not to say very dissatisfying," German Chancellor Angela Merkel said.

"There are no indications whether the United States will stay in the Paris Agreement or not."