The United States notified the United Nations on Monday of its withdrawal from the Paris climate accord, launching a formal process that will culminate in its exit exactly a year from now. They all support the agreement, the signing of which in 2016 was spearheaded by President Barack Obama, a fellow Democrat.

"President Trump made the decision to withdraw from the Paris Agreement because of the unfair economic burden imposed on American workers, businesses, and taxpayers by U.S. pledges made under the Agreement", said Secretary of State Michael Pompeo in a statement. The 2015 pact had lock in period of three years from the date of its entry into force-the Paris Agreement entered into force on November 4, 2016. He had also alleged, wrongly, that the accord favoured India and China and that India had demanded, and was granted, billions of dollars to cut its greenhouse gas emissions. "It won't happen as long as the world's second-largest climate polluter is backsliding on the climate pledge it has made to the rest of the world", Mitch Bernard, president of the Natural Resources Defense Council said in a statement.

The move further isolates the United States administration as the only national government in the world that officially turned its back on global efforts to cut greenhouse gas emissions and limit global temperature rise "well below" 2C.

The climate agreement, which went into force November 4, 2016, committed countries that signed the measure to take certain voluntary steps to reduce greenhouse gas emissions.

The decision to withdraw from the Paris Agreement has been widely slammed and is set to isolate the U.S. even further.

"Governments are moving in the right direction, but nowhere near enough, so hopefully they will be willing to take on much stronger commitments" in next month's United Nation's climate summit in Spain, said Robert Watson, lead author of the report by the nonprofit Universal Ecological Fund.

Mr Trump declared that America would withdraw from the Paris accord on climate change, in 2017. He's largely stopped making the brazenly inaccurate claim that climate change is a "hoax", instead making a more nuanced but also spurious claim that climate policy would mean wrecking the economy.

Today's move has been expected ever since President Donald Trump stood in the White House Rose Garden on 1 June 2017, and blasted the global climate pact as a bad trade deal for the United States.

While the USA exit from the 2015 agreement is not unexpected there are concerns about how it will impact the global effort to slowdown warming and effectively tackle climate change. The Paris Agreement enshrines keeping temperature rise by the end of the century "well below 2°C" as the goal for global efforts to tackle climate change. It won't happen without US leadership.

The reason for the long-term emissions drop is because the USA is using less coal and has tightened air quality standards, while Trump is pushing for more coal and loosening those standards, said Michael Gerrard, who heads Columbia Law School's climate change legal center. We're already about 1 degree above pre-industrial levels, with most of that increase coming in the last 35 years.

On the contrary, Senator Ted Cruz from Texas defended President Trump by saying the Paris agreement is unfair and "economically devastating".

He announced the U.S. would cease all implementation of non-binding elements of the agreement and begin negotiations either to re-enter the Paris accord or to have a new agreement "on terms that are fair to the United States, its businesses, its workers, its people, its taxpayers".