American students protest outside the UN climate talks during the COP22 international climate conference in Marrakesh in reaction to Donald Trump's victory in the US presidential election. Picture: Fadel Senna

Mr Trump “cannot prevent the implementation” of the landmark Paris pact, inked in the French capital last December, said Segolene Royal, France’s environment minister and outgoing head of the UN climate forum.

“As I speak, 103 countries representing 70 per cent of (greenhouse gas) emissions have ratified it, and he cannot — contrary to his assertions — undo the Paris Agreement,” she told French radio station RTL.

Mr Trump has described global warming as a “hoax” perpetrated by the Chinese government, and has said at different times that he would “renegotiate” or “cancel” the 196-nation deal.

Ms Royal noted that under the terms of the agreement, the United States must wait at least three years before seeking to withdraw.

UN climate chief Patricia Espinosa congratulated Mr Trump on his victory in a statement.

“We look forward to engaging with his administration to take the climate action agenda forward for the benefit of the peoples of the globe,” she said.

Diplomats and business leaders invested in moving the global economy from fossil fuels to renewables hope the gathering momentum of that transition will carry the United States with it, regardless of Mr Trump’s views.

“President-elect Donald Trump has been the source of a lot of bluster on climate change over the last year,” said Hilda Heine, president of the Marshall Islands, whose nation is slowly disappearing under the waves.

UK Front pages. Donald Trump voted President of the United States.Source:Supplied

“But now that the election campaign has passed,” Ms Heine added in her statement, “I expect he will realise that climate change is a threat to his people and to whole countries which share seas with the US, including my own.” France’s top climate negotiator Laurence Tubiana said that Mr Trump could not defy science.

“The laws of physics are the laws of physics, and the reality of climate change is not going to change because of the US elections,” she told AFP.

BACK TO BEING A CLIMATE VILLAIN?

America is the world’s second-largest greenhouse gas polluter after China, representing some 13 per cent of emissions.

Mr Trump’s threats, if carried out, would recast the United States as a climate villain, which is how it was widely perceived after George W Bush refused to ratify the Kyoto Protocol in 2001.

The Obama administration has been an ardent champion of the Paris Agreement, a role Mr Trump’s Democratic rival, Hillary Clinton, had vowed to continue.

Some green groups were far less diplomatic in their reaction to the surprise outcome of the US vote.

“(Mr) Trump’s election is a disaster, but it cannot be the end of the international climate process,” said May Boeve, executive director of 350.org, a global group pushing for divestment from fossil fuels.

“Our work becomes much harder now, but it’s not impossible, and we refuse to give up hope.”

A supporter celebrates as returns come in for Republican US presidential nominee Donald Trump during an election night rally in Manhattan.Source:Picture Media

The business community echoed diplomats, suggesting that a Trump administration will stay in line with international efforts as a matter of national interest.

“He wants to make America great again,” said We Mean Business, a coalition of several thousand companies and investors.

“Climate action provides the basis for new jobs and enhanced competitiveness in the industries of tomorrow,” it said in a statement, noting that the sector employs 2.5 million in the US.

Legal experts consulted by AFP said Mr Trump would have three options if he sought to unwind the US role in the UN climate process.

With one year’s notice, he could withdraw the United States from the bedrock 1992 climate convention, and in so doing sever the US tie to the Paris pact.

Secondly, the Paris agreement itself makes provision for parties to withdraw from it, but notice can only be given three years after its entry into force, which came last Friday.

Finally, he could abandon or ignore the US’s national emissions reduction targets, which contribute to the overall international effort.