US President Trump signs order to roll back Obama's climate policies

"As long as natural gas is cheaper than coal to produce electricity, it will capture larger and larger shares of the market, and that will drive Carbon dioxide emissions down", Ringel said.

"President Trump's executive order rolls back one of the most draconian overreaches in the history of big government".

Hours after President Donald Trump signed an executive order seeking to undo his predecessor's efforts to curb climate change, his administration has asked a federal appeals court to postpone ruling on lawsuits over Obama-era restrictions on carbon emissions.

And that would counter Pruitt's pledge Tuesday to not "pick winners and losers" but let the power industry pick the best fuel source for itself, the justification he used for rolling back the Obama era regulations.

"When I was an EPA employee, I collaborated on various environmental protection assignments in the same Washington office from which Donald Trump today announced his rollback of the past administration's quite modest global climate change measures", Chris Sproul, a former federal EPA employee told Business Insider in an email. The order instructs the EPA and Army Corps of Engineers to review a rule that redefined "waters of the United States" protected under the Clean Water Act to include smaller creeks and wetlands.

China is keen to be seen leading the way in reducing climate change which Trump has in the past dismissed as a "hoax".

Last year, Chinese coal consumption fell 4.7 percent, its third annual decline, according to official data.

"It will make it virtually impossible" for the USA to meet its target, said Bob Ward, a climate specialist at the London School of Economics, of Trump's executive order.

The current executive order nullifies six executive orders that Obama signed.

"Fights in the courts and executive orders really create a lot of uncertainty", Kelly said. "If fully implemented, the Clean Power Plan would have completely decimated West Virginia's vital coal industry while having no meaningful climate impact".

Christiana Figueres, former executive secretary of the UN Framework Convention on Climate Change, said Trump's action risked putting the United States on the back foot.

Environmentalists fear the steps may be a prelude to a US withdrawal from the landmark 2015 Paris climate accord and said the measures will make it hard, if not impossible, for the meet its commitments under that agreement.

The change in position by the Trump administration could leave attorneys for progressive states, green groups and other organizations fighting for the right to defend the federal rules despite a federal government no longer wanting them.

But even Mr Murray conceded that he did not expect Mr Trump's order to return coal mining numbers to their former strength.

An analysis by the consulting firm Rhodium Group finds that Trump's order is likely to have little impact on US greenhouse gas emissions in the next two years.

Environmental groups vowed to fight the order.