Murray Energy CEO Robert Murray said though he’s encouraged by President Donald Trump’s assault on what he called fraudulent green legislation, he doubts many mining jobs will be coming back.

Murray, 77, founder of the largest privately held coal mining company in the U.S., told Monday’s Guardian he is confident the president will follow through on promises to scrap the clean power plan, former President Barack Obama’s signature climate change plan, which was designed to cut carbon emissions from the power sector by 32 percent by 2030. Murray blamed the plan for the closure of 411 coal-fired power plants and a freeze on new construction.

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Murray, who accused the Obama administration of trying to destroy the coal industry, visited the White House last month and presented Trump with a plan for overturning many of the previous administration’s protections, including reclassifying carbon dioxide as a nonpollutant. He also wants Trump to level the playing field by eliminating subsidies for renewable energy sources like solar and wind.

“Barack Obama and his Democrat supporters were the greatest destroyers the United States of America has ever seen in its history,” Murray told the Guardian. “He destroyed reliable electric power in America, he destroyed low-cost electric power in America, and he attempted to totally destroy the United States coal industry.”

Coal currently provides 30 percent of the nation’s electric needs, down from 52 percent in 2009. The Mine Safety and Health Administration says the coal industry employed 98,505 people in 2015, down from 127,745 in 2008 and 250,000 in the 1970s.

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Trump, who has called climate change a “hoax,” Monday signed a series of measures that cancel federal regulations and cut red tape.

During the presidential campaign, he pledged to bring back coal jobs and repeated those promises last week at a rally in Louisville, Kentucky. The budget he presented earlier this month gutted the Environmental Protection Agency.

Murray said he told the president to “temper his expectations” when it comes to restoring mining industry jobs, however, because many of them were lost to technology, not regulation.

“He can’t bring them back,” Murray said.

The administration is expected to lift a moratorium on federal coal mining leases Tuesday, but Robert Godby, a professor of energy economics at the University of Wyoming, told Bloomberg no one is looking for new coal reserves.

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