The White House is all set to get rid of a piece of regulation that had long been billed as former President Barack Obama’s most important effort to combat climate change. The head of the Environmental Protection Agency, Scott Pruitt, said he will sign the paperwork Tuesday to formally propose repealing the Clean Power Plan that sought to cut back on greenhouse gas emissions from power plants.

Speaking at an event in eastern Kentucky, Pruitt said the government overstepped its bounds by issuing regulation that would have forced states to move away from coal-fired power plants. “The EPA and no federal agency should ever use its authority to say to you we are going to declare war on any sector of our economy,” Pruitt said alongside Senate Majority Leader Mitch McConnell. “That rule really was about picking winners and losers.” The conclusion? “The war on coal is over.”

The decision isn’t exactly a surprise considering it was a centerpiece of Trump’s campaign and several news outlets reported last week on the draft repeal proposal that claimed the Obama-era rule violated federal law and would have cost consumers as much as $33 billion. “Under the interpretation proposed in this notice, the CPP exceeds the EPA’s statutory authority and would be repealed,” the proposal reads. “The EPA welcomes comment on the legal interpretation addressed in this proposed rulemaking.” Pruitt isn’t exactly new to this fight either. He was one of around two dozen attorneys general who sued the previous administration to put a stop to the limits on carbon emissions.

.@EPAScottPruitt: "The war on coal is over." - Trump Administration to undo Obama climate change carbon regulations #Winning #MAGA pic.twitter.com/pTDWWsdvay — Matt Batzel (@MattBatzel) October 9, 2017

Environmental groups quickly criticized the announcement as they praised the rule that would have reduced emissions from power plants by 32 percent below 2005 levels by 2030. “No matter who is in the White House, the EPA is legally required to limit dangerous carbon pollution, and the Clean Power Plan is an achievable, affordable way to do that,” said Sierra Club Executive Director Michael Brune. In contrast, the National Rural Electric Cooperative Association, which was one of the groups that challenged the Obama-era regulation, said getting rid of the rule would allow plants to provide “reliable, affordable power” to customers.

Clean Power Plan repeal: "A dangerous move by an admin that continues to value polluter $ over people" https://t.co/xfmzXJIwFg @maryannehitt — Sierra Club (@SierraClub) October 9, 2017

The administration is expected to argue on Tuesday that the rule actually represented an overreach of federal law because it set standards that power plants couldn’t reasonably be expected to meet. But eliminating the Clean Power Plan also makes it less likely the United States could meet the goals set out by the Paris climate accord, which Trump has promised to abandon.

The change would not be imminent. The repeal proposal will first go through a period of public comment to help determine how it should be replaced. There is no set timeline on how long that could take but it’s likely to be slowed down by a series of expected legal challenges from environmental groups and Democrats that may very well end up in the Supreme Court.