The United States formally exited the Paris Climate Agreement on Wednesday amid election uncertainty, three years after President Donald Trump announced his intent to remove the country from participating in the landmark global pact to reduce greenhouse gas emissions.
President Trump originally announced his intention to withdraw from the agreement in 2017 and formally notified the United Nations last year.
The US exited the pact after a mandatory year-long waiting period that ended on Wednesday.
The official withdrawal from the Paris Climate Accord comes as the US is in the middle of a tight Presidential election, with the race to the White House between President Donald Trump and his Democratic rival Joe Biden poised for a photo-finish with million of votes still being counted.
The US had signed the Paris Agreement on April 22, 2016 and expressed its consent to be bound by the Agreement by acceptance in September 2016.
A letter to the Secretary-General from US Secretary of State Mike Pompeo, dated November 4, 2019 said, 'this letter constitutes notification by the United States of America of its withdrawal from the Paris Agreement.
'Pursuant to Article 28, paragraph 2, of the Paris Agreement, the withdrawal of the United States from the Paris Agreement shall take effect upon expiry of one year from the date on which you receive this notification of withdrawal.'
The historic accord seeks to limit global warming to less than 2 degrees Celsius, the value that climate scientists have determined will have disastrous consequences if exceeded.
Trump has repeatedly criticised the agreement as economically detrimental and claimed it could cost the country 2.5 million jobs by 2025.
He also said it gave other major emitters, like China and India, a free pass.
The US is the only country to withdraw from the global pact. It can still attend negotiations and give opinions, but is relegated to 'observer status'.
Trump stated that he intended to renegotiate the details of the United States' membership within the Paris Agreement that can better protect US workers in industries like coal, paper, and steel.
UN Secretary-General Antonio Guterres had earlier called the decision by the US to withdraw from the Paris Agreement on climate change as a 'major disappointment for global efforts to reduce greenhouse gas emissions and promote global security'.
"The Paris Agreement was adopted by all the world's nations in 2015 because they recognise the immense harm that climate change is already causing and the enormous opportunity that climate action presents. It offers a meaningful yet flexible framework for action by all countries," Guterres had said.
The UN Chief had expressed confidence that cities, states and businesses within the United States -- along with other countries -- will continue to demonstrate vision and leadership by working for the low-carbon, resilient economic growth that will create quality jobs and markets for twenty-first century prosperity
The US is the second leading producer of all carbon dioxide emissions globally, behind China.
The US State Department last year said, 'the United States has reduced all types of emissions, even as we grow our economy and ensure our citizens' access to affordable energy.
'Our results speak for themselves: U.S. emissions of criteria air pollutants that impact human health and the environment declined by 74% between 1970 and 2018. U.S. net greenhouse gas emissions dropped 13% from 2005-2017, even as our economy grew over 19 percent.'
'In international climate discussions, we will continue to offer a realistic and pragmatic model -- backed by a record of real world results -- showing innovation and open markets lead to greater prosperity, fewer emissions, and more secure sources of energy,' the Department had said.
Whether the US exit turns out to be brief or lasting depends on the outcome of the presidential contest, The Washington Post said.
A possible second Trump term would make clear that an international effort to slow the Earth's warming will not include the US government.
Democratic presidential candidate Joe Biden, meanwhile, has vowed to rejoin the Paris accord as soon as he is inaugurated and to make the US a global leader on climate action.
"Biden has vowed to re-enter the Paris accord if elected, a move that could take less than six months," Varun Sivaram, a senior research scholar at Columbia University's SIPA Center on Global Energy Policy, told ABC News.
"Over the last four years, the Trump administration has sharply diminished the United States' standing in the world," in terms of environmental policy, Sivaram said.
While Biden's climate plan has been recognised as the most ambitious the US has ever proposed, it still may not hit the mark, according to some critics.
Republicans have criticised Biden's climate plan as being too expensive, with Vice President Mike Pence describing it as 'a $2 trillion version of the Green New Deal' during his debate with Democratic rival Senator Kamala Harris last month.