The U.S. Environmental Protection Agency will propose repealing the Clean Power Plan—the Obama administration’s centerpiece regulation to fight climate change—and plans to solicit input on a rule to replace it, according to an EPA document seen by Reuters.

The decision marks the agency’s first formal step to sweep away the rule intended to cut carbon emissions from power plants, after President Donald Trump signed an executive order in March launching the EPA’s review.

The Republican president has expressed doubts about the science of climate change and has blamed former Democratic President Barack Obama’s efforts to cut carbon emissions for hurting the coal mining and oil drilling industries.

The Clean Power Plan, or CPP, was challenged in court by 27 states after Obama’s administration launched it in 2015. It is currently suspended by the D.C. Circuit Court of Appeals, which set a deadline of Friday for a status report from the EPA on how it plans to proceed.

The EPA document, distributed to members of the agency’s Regulatory Steering Committee, said the EPA “is issuing a proposal to repeal the rule.”

The agency now intends to issue what it calls an Advanced Notice of Proposed Rulemaking to solicit input as it considers “developing a rule similarly intended to reduce CO2 emissions from existing fossil fuel electric utility generating units.”

The document did not provide any details of the potential new rule.

The EPA did not immediately respond to a request for comment.

The CPP was designed to lower carbon emissions from existing U.S. power plants by 2030 to 32% below 2005 levels.

It was seen as the main tool for the United States to meet emissions cuts it promised in the Paris Climate Agreement, a global pact to fight climate change.

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The Trump administration has announced it will withdraw the United States from the Paris deal—which it said would cost the U.S. economy trillions of dollars without tangible environmental benefits—in a process that could take years.

Industry sources following the rulemaking process expect the proposal to repeal and replace the Clean Power Plan to be released as soon as the end of this week.

Janet McCabe, who headed the EPA’s Office of Air and Radiation under Obama, said an advanced notice of proposed rulemaking could take years—meaning the replacement for CPP could be a long way off.

“It certainly will draw the process out,” she said.

Some conservative groups have urged the EPA to scrap the CPP without replacing it, effectively ending U.S. regulation of carbon emissions. But some industry groups want a replacement to give utilities regulatory certainty and avoid possible lawsuits by environmental groups.