There has been widespread international condemnation of President Trump’s announcement that the US is withdrawing from the 2015 Paris climate agreement.
UN chief Antonio Guterres’s spokesman called it “a major disappointment” while the European Union said it was “a sad day for the world”.
However, senior Republicans and the US coal industry backed the move.
Mr Trump said the accord “punished” the US and would cost millions of American jobs.
In an address at the White House, he said he was prepared to negotiate a new agreement or re-enter the accord on improved terms.
“I was elected to represent the citizens of Pittsburgh, not Paris,” he said.
The Paris agreement commits the US and 187 other countries to keeping rising global temperatures “well below” 2C above pre-industrial levels and “endeavour to limit” them even more, to 1.5C.
Only Syria and Nicaragua did not sign up to the deal.
Mr Trump characterised the Paris agreement as a deal that aimed to hobble, disadvantage and impoverish the US.
He claimed the agreement would cost the US $3tn (£2.3tn) in lost GDP and 6.5 million jobs – while rival economies like China and India were treated more favourably.
“In order to fulfil my solemn duty to protect America and its citizens, the United States will withdraw from the Paris climate accord… but begin negotiations to re-enter either the Paris accord or a really entirely new transaction on terms that are fair to the United States,” he said.
“We don’t want other leaders and other countries laughing at us any more – and they won’t be,” he said.
Mr Trump did not give a timescale for US withdrawal, but White House sources had earlier suggested it could take up to four years.
Former US President Barack Obama, who agreed to the Paris deal, immediately criticised the move, accusing the Trump administration of “rejecting the future”.
The leaders of France, Germany and Italy issued a joint statement rejecting a renegotiation of the agreement.
“We deem the momentum generated in Paris in December 2015 irreversible and we firmly believe that the Paris agreement cannot be renegotiated, since it is a vital instrument for our planet, societies and economies,” it said.
Canada was “deeply disappointed” by President Trump’s decision, Prime Minister Justin Trudeau said.
This was echoed by UK Prime Minister Theresa May, who expressed her disappointment and told Mr Trump in a phone call that the deal protects the “prosperity and security of future generations”.
Leaders of the Nordic nations – Sweden, Finland, Denmark, Norway, and Iceland – also condemned the move.
A United Nations spokeswoman said it was a “major disappointment for global efforts to reduce greenhouse gas emissions and promote global security”.
source: bbc.com