Generation of electricity is the second largest source of carbon dioxide and other planet-warming gases in the United States. E. P.

A. administrator Lee Zeldin speaking next to President Trump in the Oval Office earlier this year. Mr. Zeldin is expected to announce on Monday that the agency will no longer limit greenhouse gas emissions from power plants. Sept. 13, 2026 The Trump administration plans to announce Monday that the United States will no longer limit the planet-warming pollution that power plants pump into the air while burning coal and gas, according to two people familiar with the proposal. The shift by the Environmental Protection Agency would complete the administration’s erasure of the most consequential climate policies of Presidents Joseph R. Biden Jr. and Barack Obama.

If the move survives expected legal challenges, it could also prevent future administrations from regulating greenhouse gas emissions from power plants. The power sector is the second largest source of carbon dioxide and other greenhouse gases in the United States. This pollution accumulates in the atmosphere, where it traps the sun’s heat, raising temperatures and supercharging extreme weather events around the globe.

Lee Zeldin, the E. P. A. administrator, is expected to announce the change during a meeting of energy ministers from the Group of 20 nations in Houston, according to the two people familiar with the matter, who requested anonymity to describe the proposal before it is made public.

Representatives for the E. P. A. did not immediately respond to a request for comment late Sunday evening.

Environmentalists and energy experts have opposed the move, which has been in the works since last spring. They have noted that if the U.S. power sector were its own country, it would be the fifth-largest climate polluter in the world after China, the entire United States, India and Russia. President Trump has derided climate change as a “hoax,” and in his second term, the E.

P. A. has systematically dismantled policies aimed at slowing global warming that have been criticized as costly by oil, gas and coal companies. The administration has tried to make it easier and cheaper to produce and use fossil fuels, especially to generate electricity that can meet growing demand from artificial intelligence data centers.

Earlier this year, the E. P. A. eliminated greenhouse gas standards for car tailpipes and eased restrictions on planet-warming chemicals used in air-conditioners and refrigerators.

Most consequentially, the agency repealed the scientific determination that gave it the legal authority to create climate regulations in the first place. Under the plan expected Monday, power plants would still be subject to some limits on mercury, arsenic and other contaminants, though the E. P.

A. has already loosened restrictions on how much mercury they can emit. The Biden administration’s climate rules for power plants, finalized in 2024, applied to coal-burning plants that were in operation and gas-burning plants that could be built in the future. To comply, coal plants could have installed technology to trap carbon emissions before they are released into the air and store them deep underground.

Gas plants could have operated on cleaner fuels like hydrogen, which produces no emissions when burned. The Biden administration estimated that the regulation would also prevent other pollutants, such as soot, from escaping into the air, resulting in $120 billion in public health benefits by 2047. It projected that in 2035 alone, the rule would prevent up to 1,200 premature deaths, 870 hospital and emergency room visits, 360,000 asthma attacks, 48,000 school absence days and 57,000 lost workdays.

Under the Trump administration, the E. P. A. has stopped estimating the public health benefits of reducing pollution in the cost-benefit analyses necessary for clean-air regulations.

Instead, the agency has estimated only the costs to businesses of complying with the rules. The coal in...