The Trump administration and Republicans in Congress are preparing an unusual legislative maneuver in an effort to eliminate one of the country’s most ambitious climate policies, an order that was designed to shift the auto industry toward electric cars.

They plan to vote to overturn a California ban on the sale of new gasoline-powered cars by 2035. To do it, they intend to use the Congressional Review Act, a 1996 law that permits lawmakers to reverse recently adopted regulations with a simple majority vote.

But the California ban is not a federal regulation. It’s the result of a waiver that was granted by the Biden administration under the 1970 Clean Air Act, something that has been done more than 100 times over the years by both parties. And it is not subject to congressional review, according to a 2023 decision by the Government Accountability Office.

Environmental groups and California officials say the Republican plan to try to kill the Environmental Protection Agency’s waiver with a congressional vote would be illegal.

Gov. Gavin Newsom of California, a Democrat who frequently sparred with Trump during the president’s first term and who has promoted his state as an environmental leader, declined to comment. His office referred questions to the state’s air pollution regulator, the California Air Resources Board.

David Clegern, a spokesperson for the board, said in a statement: “The Trump EPA is doing what no EPA under Democratic or Republican administrations in 50 years has ever done, and what the GAO has confirmed does not comply with the law.”

The Clean Air Act specifies that California can be allowed to enact tougher clean air standards than those set by the federal government because, historically, it has had the most polluted air in the nation. Federal law also allows other states under certain circumstances to adopt California’s standards as their own. California’s waivers have never been presented to Congress for a vote.

As the fifth-biggest economy in the world, California exerts significant market influence. Eleven other states have said they will follow California’s lead and ban the sale of new gas-powered cars by 2035. Together, they make up nearly half the U.S. auto market.

Because of that, Republicans argue that California is setting a de facto national policy that should be reviewed by Congress. The Trump administration, which is dismissive of climate change and wants to increase the use of fossil fuels, has made the California waiver a top target.

Trump has signed executive orders and introduced policies to promote fossil fuels at a rapid pace, frequently barreling through guardrails. Ann Carlson, a professor of environmental law at the University of California, Los Angeles, called the auto waiver strategy part of “a pattern with this administration of saying ‘We want to destroy something, and we’re going to take the fastest path to do so whether or not it complies with the law.’”

But Scott Segal, a partner at Bracewell, a law firm that represents fossil fuel companies, said it is “entirely appropriate” for Congress to weigh in, given that so many other states adopt California’s standards.

“It’s California’s request that it be allowed to regulate, and regulate in a way that drags a bunch of other states with it,” Segal said. “It’s a market-setting, insidious regulation.”

Lee Zeldin, the EPA administrator, could withdraw the waiver. But that would require months of public notice and comment.

Instead, Zeldin last week submitted the automobile waiver to Congress along with two other California waivers approved by the EPA last year. One requires that half of all new heavy-duty vehicles sold in the state to be electric by 2035, and the other restricts nitrogen dioxide and particulate matter pollution from cars and trucks. He called them “extremely consequential actions that have massive impacts and costs across the entire United States.”