Energy giant Exxon Mobil has asked the Trump administration not to scrap US participation in the landmark Paris climate agreement, running counter to White House moves on carbon emissions.

The news came as President Donald Trump on Tuesday unveiled a new executive order that could roll back some of the previous Democratic administration's policies aimed at curbing greenhouse gas emissions and climate change.

In a March 22 letter to Trump energy advisor G David Banks, Exxon's head of environmental policy and planning, Peter Trelenberg, praised the 2015 Paris Agreement as the first to tackle emissions by both the developed world and developing countries such as China and India.

China is the world's largest greenhouse gas emitter and India could overtake the United States as the world's second-largest by mid-century, Trelenberg said in the letter.

The US is poised to compete in energy markets while abiding by the agreement's calls for emissions reductions in part due to its increasing reliance on natural gas, which produces energy with fewer emissions, Trelenberg said.

"It is prudent that the United States remain a party to Paris Agreement to ensure a level playing field so that global energy markets remain as free and competitive as possible," wrote the executive from Exxon Mobil, the world's largest publicly-traded energy firm.

Fighting climate change will require technological advances, the letter said, and the United States should advance policies that promote this.

The Trump administration has not said whether it will pull out of the Paris agreement but on Tuesday unveiled policies that could move the US away from meeting internationally agreed emissions targets.

The Republican president said the US was ending a "war on coal," claiming that lifting regulations on the industry would lead to new jobs.

He ordered a review of emissions limits on coal-fired power plants and restrictions on federal leasing for coal production.

The Trump administration is linked to Exxon Mobil through Secretary of State Rex Tillerson, who served as the energy giant's chief executive before becoming America's top diplomat.

Several states have sued the energy company for allegedly deceiving the public about the role of fossil fuels in global warming.

But Tillerson himself is credited with steering ExxonMobil towards public acceptance of the science of climate change.

source: AFP