The Trump administration on Friday officially told the United Nations that the US intends to pull out of the 2015 Paris Climate Agreement, but left the door open to re-engaging in global warming talks if the terms suit the United States.
The State Department said in a press release the United States would continue to participate in United Nations climate change meetings during the withdrawal process, which is expected to take at least three years as the announcement doesn't formally start the process of the US getting out of the voluntary agreement.
Still, the department described its communication as a ''strong message'' to the world, following President Donald Trump's decision in June to leave the accord.
"The United States supports a balanced approach to climate policy that lowers emissions while promoting economic growth and ensuring energy security," the department said in the release.
The next meeting is in Bonn, Germany, in November. Trump is ''open to re-engaging in the Paris Agreement if the United States can identify terms that are more favourable to it, its business, its workers, its people and its taxpayers,'' the department said.
Nigel Purvis, who directed US climate diplomacy during the Bill Clinton and George W Bush administrations, told AP, ''The State Department is telling that UN what the president already told the world on June 1 and it has no legal effect.''
Purvis said countries can't withdraw from new international agreements, including the Paris climate one, until three years after they go into effect - and even after that the process takes a year. The Paris agreement went into effect on 4 November 2016.
The State Department cited the same timeline, saying it can officially start withdrawing as soon as November 2019. That means the earliest the US can be out of the climate agreement is 4 November 2020 Ė the day after the next presidential election.
During a visit last month to Paris to meet French President Emmanuel Macron, the two discussed the deal and Trump told reporters, "Something could happen with respect to the Paris accords, let's see what happens."
Under the agreement, countries set their own national plans for cutting climate emissions. That means Trump can come up with different targets for the United States than those set by President Barack Obama. But Trump can't unilaterally change the text of the Paris deal.
United Nations spokesman Stephane Dujarric confirmed that Secretary-General Antonio Guterres received ''a communication'' from US Ambassador Nikki Haley ''expressing the intention of the United States to exercise its right to withdraw from the Paris Agreement, as soon as it is eligible to do so under the Agreement, unless it identifies suitable terms for reengagement''.
He added, ''The secretary-general welcomes any effort to re-engage in the Paris Agreement by the United States.'' he said.
Dujarric reiterated Guterres' 1 June statement calling the US decision to withdraw ''a major disappointment for global efforts to reduce greenhouse gas emissions and promote global security''.
''It is crucial that the United States remains a leader on climate and sustainable development,'' Dujarric said. ''Climate change is impacting now. He (Guterres) looks forward to engaging with the American government and all other actors in the United States and around the world to build the sustainable future for our children and future generations.''
Under Obama, the US agreed to reduce polluting emissions more than a quarter from 2005 levels by the year 2025. And no matter what the US does, the Paris agreement remains in effect because enough other countries ratified it.
The Paris agreement aims to prevent the earth from heating up by 2 degrees Celsius since the start of the industrial age. The world has already warmed about 1.1 degrees Celsius since the Industrial Revolution. The overwhelming majority of scientists say the burning of coal, oil and gas is causing the earth's climate to change because of heat-trapping gases.
This is not the first time the US is opting out of an international climate pact. It had earlier pulled out of the Kyoto Protocol saying emerging economies do not have quantified emission targets.
But unlike the Paris accord, the US had not ratified the Kyoto Protocol adopted in 1997. The Kyoto pact had binding targets for emission reductions only for the 38 developed countries. The Paris deal is more comprehensive because it has a universal application.