Trump said the US would withdraw from the Paris Agreement, secured in the French capital in December 2015, which commits countries to curbing rising global temperatures.
Trump lambasted the agreement as being more about keeping America down and less about the environment.
“This agreement is less about the climate and more about other countries obtaining a financial advantage over the United States,” Trump said.
The president said the agreement gives “countries an economic edge over the United States,” adding, “that’s not going to happen while I’m president.”
“As of today, the United States will cease all implementation of the nonbinding Paris accord,” Trump added.
He also suggested that renegotiating re-entry was not a major priority.
“If we can, great. If we can’t, that’s fine,” Trump said.
By abandoning the world’s chief effort to slow the tide of global warming, Trump was fulfilling a top campaign pledge but he was also breaking from many of America’s staunches allies, who have expressed alarm about the decision.
The US is the world’s second-largest emitter of carbon, following only China.
Supporters of the accord condemned Trump’s move as an abdication of American leadership and an international disgrace.
Former President Barack Obama immediately criticised the Trump administration, saying it is joining “a small handful of nations that reject the future” by withdrawing from the Paris climate change pact.
The former president said in a statement that Trump’s decision reflects “the absence of American leadership.”
Democratic senator Bernie Sanders was also vocal in condemning Trump’s decision to exit the Paris accord.
“At this moment, when climate change is already causing devastating harm around the world, we do not have the moral right to turn our backs on efforts to preserve this planet for future generations,” Sanders said.
Prime Minister Malcolm Turnbull is resisting pressure from within his own ranks to reconsider Australia’s commitment to the Paris agreement.
Labor leader Bill Shorten says the US has failed to stand by its 2015 promise to stick to the global deal and has urged the prime minister to press Trump to reconsider the decision.
Two Liberals, Eric Abetz and Craig Kelly, have called for a rethink of Australia’s involvement in the climate pact in the wake of the US decision because of its potential impact on business.
The prime minister told reporters in Singapore on Friday, where he is attending security talks, the government will not be following the US.
“We are committed to the Paris agreement,” he said.
“We are on track to meet our 2030 targets of a reduction in emissions by 26 per cent to 28 per cent from 2005 levels – and I should say we are doing well.”
Kelly hailed Trump’s decision and, while acknowledging Australia’s commitment, said it was “something we have to monitor”, particularly in regard to the impact on business competitiveness.
“The idea we can lock something in and leave it for a decade is just not the reality of the real world,” Kelly told Sky News on Friday.
Abetz says a report by chief scientist Alan Finkel on Australia’s electricity sector should be delayed while a thorough assessment is made of the US decision’s impact.
However, Turnbull says the report will be presented as planned next week when he meets with the premiers in Hobart.
“We are committed to ensuring that Australians have affordable and reliable energy and that we meet our emission reduction targets,” Turnbull said.
More than 190 countries signed onto the deal, with 146 proceeding to ratify the agreement.
Foreign Minister Julie Bishop will get the chance to discuss the issue with US Secretary of State Rex Tillerson in Sydney next week.
Labor foreign affairs spokeswoman Penny Wong says Australia should make its views “absolutely clear” but doubted the coalition has the policies to meet Australia’s reduction targets.
Australia ratified the Paris deal the day after Trump was elected in November.
The South Australian Environment Minister, Ian Hunter, said that while Trump didn’t accept the realities of climate change, many states and cities did.
He said in an email to “stakeholders” sent out today that Adelaide Oval would glow green tonight to “show our State’s support for effective action on climate change”.
– with AAP
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