From world leaders to prominent intellectuals, many urge the US to keep its commitment to the Paris climate change deal.

Reports emerged on Wednesday that President Donald Trump is set to pull the United States out of the landmark Paris Agreement on climate change in what is seen as a huge blow to efforts aimed at cutting global emissions.

If the US withdraws from the Paris Agreement, it will join Nicaragua and Syria as the only countries to have not signed on to the deal, which aims to limit the increase in global temperature to two degrees Celsius above pre-industrial levels by 2100.

Trump, who has previously called climate change a “hoax” and a Chinese-created concept, tweeted late on Wednesday that he would announce his decision regarding the deal on Thursday at 19:00 GMT.

During his presidential campaign, the Republican vowed to “cancel” the agreement, adding he would “stop all payments of US tax dollars to UN global warming programmes” within his first 100 days in office.

Trump’s promise has drawn condemnation from many corners of the world. Here are some of the seven strongest warnings given by prominent individuals and groups to the US president regarding the potential withdrawal from the deal:

‘Not a fairy tale’

In Europe, many leaders issued strong rebukes over the reported US withdrawal, taking issue with the Trump administration’s climate-sceptic stance.

“Climate change is not a fairy tale,” European Parliament President Antonio Tajani said on Wednesday.

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“People die or are obliged to leave their homes because of desertification, lack of water, exposure to disease, extreme weather conditions,” he said. “If we don’t act swiftly and boldly, the huge human and economic cost will continue to increase.”

This notion — 'I am Trump. I am American. America first, so I'm going to get out of it.' — that is not going to happen … Not everything in international agreements is fake news. Jean Claude Juncker, European Commission president

European Commission President Jean-Claude Juncker warned that quitting the Paris Agreement is not a straightforward process.

“The Americans can’t just leave the climate protection agreement,” Juncker told a conference in Germany on Wednesday. “Mr Trump believes that because he doesn’t know the details.”

Juncker added that it is the “duty of Europe” to tell the US how the agreement works.

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During last week’s G7 meeting, attended by Trump for the first time, German Chancellor Angela Merkel called the discussions on climate change “very difficult – not to say very unsatisfactory”.

Merkel said European leaders “made it clear that we want the US to stick to its commitments”.

‘A betrayal’

Other leaders and diplomats warned Trump about the impact of withdrawal – not just on climate change, but also on US standing in the world.

Ethiopian diplomat Gebru Jember Endalew, a key figure in climate change negotiations for the “48 least developed countries” group, said it would be a “betrayal” for the US to abandon the agreement.

“If the US withdraws, it’s a betrayal to the global community – especially the least developed countries and the most vulnerable groups of countries,” Endalew said.

Chai Qimin, of the Chinese government-funded National Centre for Climate Change Strategy and International Cooperation, warned this month that leaving the agreement would “harm mutual trust” between world powers.

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“President Xi [Jinping] and our ambassador to the United Nations have said several times that withdrawing from the Paris Agreement is irresponsible, which will harm the mutual trust in the multilateral mechanism.”

Xi on Wednesday reaffirmed his commitment to uphold the Paris Agreement, saying the world must “protect the global governance achievements contained” within the agreement.

‘World’s most dangerous party’

Noam Chomsky, the renowned US academic and intellectual, has in the past sharply criticised the Republican Party for its approach to climate change, calling it “the most dangerous organisation in the world”.

In a recent interview with Democracy Now, Chomsky defended his self-described “outrageous statement”, citing what he calls the party’s dedication and commitment “to the destruction of organised human life on Earth”.

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At least 22 Senate Republicans and a dozen House Republicans have expressed support for a plan to pull out of the Paris Agreement.

Oklahoma Republican James Inhofe, a climate change denier, led the senators in drafting a letter (PDF) calling for “a clean break” from the accord.

“We have been encouraged by the steps you have taken to reduce the regulatory burdens facing the country,” the senators said.

But others within the party, including former presidential candidate Mitt Romney, have expressed concern:

Affirmation of the #ParisAgreement is not only about the climate: It is also about America remaining the global leader. — Mitt Romney (@MittRomney) May 31, 2017

‘Really stupid’

Hillary Clinton, former US secretary of state and Trump’s Democratic rival in November’s election, recently said it would be “incredibly foolish” and “totally incomprehensible” to pull out of the agreement.

“What’s really stupid about [withdrawing from the agreement] is that they are throwing out the economic opportunities that being part of the Paris Agreement provide for the United States,” Clinton said at a technology conference in southern California on Wednesday.

A number of other Democrats have taken to Twitter to express their concern about the possible withdrawal.

Climate change is an existential threat to our future—staying in #ParisAgreement is the best way to protect our children & global leadership — Joe Biden (@JoeBiden) May 31, 2017

.@POTUS' decision to support a dirty energy agenda & pull out of #ParisAgreement is a grave threat to our planet. https://t.co/qMgx15EDlV — Nancy Pelosi (@SpeakerPelosi) May 31, 2017

But we'll take matters into our own hands. I plan to sign an executive order maintaining New York City’s commitment to the Paris Agreement. https://t.co/8oByikDt7C — Mayor Bill de Blasio (@NYCMayor) May 31, 2017

‘No choice but to resign’

Tech entrepreneur Elon Musk, chief executive of Tesla and SpaceX, has threatened to quit his role on White House advisory councils if Trump withdraws the US from the agreement.

“[I] don’t know which way Paris will go, but I’ve done all I can to advise directly to POTUS, through others in [the White House] that we remain,” Musk tweeted on Wednesday.

In response to a question about what he plans to do if Trump does pull out of the agreement, Musk said he would “have no choice but to depart counsels”.

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In April, more than 15 tech and energy companies including Apple, Google and Shell, signed a letter (PDF) to the president expressing support for US participation in the agreement.

“We urge that the United States remain a party to the Paris Agreement, work constructively with other nations to implement the agreement, and work to strengthen international support for a broad range of innovative technologies,” the letter said.

‘Planet Earth First’

Activists in Italy’s capital, Rome, projected the message “Planet Earth First” on St. Peter’s Basilica last week as Trump arrived for a meeting with Pope Francis at the Vatican.

“Trump must not be allowed to shirk his moral responsibility or renege on America’s Paris commitments,” Greenpeace said in a statement following the protest.

Last month, hundreds of thousands of climate activists marched on Washington, DC, as part of the People’s Climate March. This year, the march was focussed on the “need for bold action” to address climate change, especially with an “administration more reticent to climate … than any in recent memory”.

‘Get on train or get left behind’

UN Secretary-General Antonio Guterres warned that other countries would be quick to fill a “void” if the US were to pull out of the Paris agreement.

“If one country decides to leave a void, I can guarantee someone else will occupy it,” Guterres said during an event in New York on Tuesday.

“The message is simple: The sustainability train has left the station. Get on the train or get left behind.”