WASHINGTON — Coal-fired power plants would be forced to capture smokestack emissions or shut down under a rule issued Thursday by the Environmental Protection Agency.

New limits on greenhouse gas emissions from fossil fuel-fired electric plants are the Biden administration’s most ambitious effort yet to roll back planet-warming pollution from the power sector, the nation’s second-largest contributor to climate change. The rules are a key part of President Joe Biden’s pledge to eliminate carbon pollution from the electricity sector by 2035 and economy-wide by 2050.

The rule was among four measures targeting coal and natural gas plants that the EPA said would provide “regulatory certainty” to the power industry and encourage them to make investments to transition “to a clean energy economy.” The measures include requirements to reduce toxic wastewater pollutants from coal-fired plants and to safely manage coal ash in unlined storage ponds.

EPA Administrator Michael Regan said the rules will reduce pollution and improve public health while supporting the reliable, long-term supply of electricity that America needs.

“One of the biggest environmental challenges facing our nation is man-made pollution that damages our air, our water and our land,” Regan said in a speech at Howard University. “Not only is this pollution a major threat to public health — it’s pushing our planet to the brink.”

Regan called the power plant rules “a defining moment” for his agency as it works to “build a cleaner and healthier future for all of us.”

The plan is likely to be challenged by industry groups and Republican-leaning states. They have repeatedly accused the Democratic administration of overreach on environmental regulations and have warned of a looming reliability crisis for the electric grid. The rules issued Thursday are among at least a half-dozen EPA rules limiting power plant emissions and wastewater pollution.

Environmental groups hailed the EPA’s latest action as urgently needed to protect against the devastating harms of climate change.

The power plant rule marks the first time the federal government has restricted carbon dioxide emissions from existing coal-fired power plants. The rule also would force future electric plants fueled by coal or gas to control up to 90% of their carbon pollution. The new standards will avoid 1.38 billion metric tons of carbon pollution through 2047, equivalent to the annual emissions of 328 million gas cars, the EPA said, and will provide hundreds of billions of dollars in climate and health benefits, measured in fewer premature deaths, asthma cases and lost work or school days.

Coal plants that plan to stay open beyond 2039 would have to cut or capture 90% of their carbon dioxide emissions by 2032, the EPA said. Plants that expect to retire by 2039 would face a less stringent standard but still would have to capture some emissions. Coal plants that are set to retire by 2032 would not be subject to the new rules.

Rich Nolan, president and CEO of the National Mining Association, said that through the latest rules, “the EPA is systematically dismantling the reliability of the U.S. electric grid.”

He accused Biden, Regan and other officials of “ignoring our energy reality and forcing the closure of well-operating coal plants that repeatedly come to the rescue during times of peak demand. The repercussions of this reckless plan will be felt across the country by all Americans.”

Regan denied that the rules were aimed at shutting down the coal sector, but he acknowledged in proposing the power plant rule last year that, “We will see some coal retirements.”

The proposal relies on technologies to limit carbon pollution that the industry itself has said are viable and available, Regan said. “Multiple power companies have indicated that (carbon capture and storage) is a viable technology for the power sector today, and they are currently pursuing those CCS projects,” he told reporters Wednesday.

Coal provided about 16% of U.S. electricity last year, down from about 45% in 2010. Natural gas provides about 43% of U.S. electricity, with the remainder from nuclear energy and renewables such as wind, solar and hydropower.

Dan Brouillette, president and CEO of of the Edison Electric Institute, which represents U.S. investor-owned electric companies, said he was “disappointed” that the EPA “did not address the concerns we raised about carbon capture and storage.” While promising, the technology “is not yet ready for full-scale, economy-wide deployment,” said Brouillette, who served as energy secretary in President Donald Trump’s administration.