EPA Administrator Scott Pruitt on Tuesday formally proposed repealing the Obama administration’s “Clean Power Plan,” in a move to ease regulations on coal-fired power plants.

The EPA said the move to repeal would facilitate new developments of U.S. energy resources and reduce unnecessary rules that have curbed their development.

"The president made a promise to the American people that the EPA would not be an agency that picks winners and losers as we generate electricity in this country," Pruitt told Fox News' "Special Report with Bret Baier" Tuesday night. "The [Obama] administration made a commitment to declare a war on coal. And effective yesterday and today, that war is over."

The EPA said in a statement that the agency wants to declare that the Clean Power Plan exceeded the government's authority.

Pruitt announced a day earlier he planned to issue the proposal. The decision comes after President Trump in late March ordered a review of the controversial program, which was put on hold more than a year ago by the Supreme Court amid legal challenges from, among others, Pruitt himself.

Pruitt signaled Tuesday that the proposal will prompt further review and possibly a new set of rules.

"When you look at the way the [Obama EPA] conducted itself ... they acted inconsistent with the authority of the statute," Pruitt told Fox News. "They created uncertainty. Nothing has been achieved out of this rule. It’s created uncertainty across the country. So, we’ve taken the step to begin the process to rectify that [and] to provide clarity to folks across the country."

The Clean Power Plan aimed to reduce carbon emissions from coal-burning power plants by having states meet certain targets. Supporters see the plan as a critical plank in efforts to curb global warming, but critics contend it would kill thousands of jobs and take direct aim at the struggling coal sector.

The move to officially end the program was expected after the president vowed to end what he calls the “war on coal."

Pruitt could, however, face a new wave of litigation from the other side of the debate, as environmentalist groups and allied Democrats are sure to challenge the rollback.

Sierra Club Executive Director Michael Brune threatened such a court fight shortly after Monday’s announcement.

“Trump can’t reverse our clean energy and climate progress with the stroke of a pen, and we’ll fight him and Scott Pruitt in the courts, in the streets, and at the state and local level across America to protect the health of every community,” he said in a statement, calling the move “one of the most egregious attacks ever on public health, our climate, and the safety of every community in the United States.”