In its latest move to roll back environmental standards, the Trump Administration is expected to announce Wednesday that it will revoke California’s authority to set tougher pollution rules than the federal government for greenhouse gas emissions from passenger vehicles.

California’s authority dates back more than 50 years and was guaranteed under the 1970 Clean Air Act, which was signed by President Richard Nixon. Over the years, the state has set tailpipe rules that were copied by other states and eventually by the federal government, helping reduce smog dramatically.

On Tuesday, citing two sources with knowledge of the event, Bloomberg News reported that Andrew Wheeler, administrator of the U.S. Environmental Protection Agency, would be announcing plans to revoke California’s authority to set greenhouse gas standards from passenger vehicles at an event in Washington D.C. on Wednesday.

EPA officials declined to comment Tuesday. But Wheeler told the National Automobile Manufacturers Association Tuesday: “We will be moving forward with one national standard very soon.”

California officials said they will fight the move, which likely will result in a long court battle.

“California won’t ever wait for permission from Washington to protect the health and safety of children and families,” said Gov. Gavin Newsom.

“The president could learn from California,” he added. “Instead, reports today suggest that his administration will act on a political vendetta … we will fight this latest attempt and defend our clean car standards.”

Trump has denied the widely accepted consensus among scientists that the burning of fossil fuels traps heat in the atmosphere and is warming the planet. According to NASA and NOAA, the parent agency of the National Weather Service, the 10 hottest years since 1880 when modern temperature records began all have occurred since 1998.

The Clean Air Act requires California to get a waiver from the U.S. EPA to set tougher tailpipe standards than the federal government, which historically presidents have granted dozens of times.

California’s current waiver was approved during the Obama administration.

The state’s “advanced clean car” standards require new vehicles to emit 40% fewer greenhouse gases, such as carbon dioxide, by 2025, compared to 2016 levels. They have been copied by 13 other states.

Reducing greenhouse gas emissions, which come from the burning of fossil fuels, has had the effect of forcing automakers to increase gas mileage. Obama adopted California’s standard as the federal standard in 2012, which he said at the time would require an average fleet fuel economy of 54 miles per gallon on new vehicles sold in 2025.

Environmental groups hailed that as a major announcement that would dramatically reduce America’s consumption of foreign oil, cut smog and reduce the nation’s greenhouse gas emissions.

But the Trump EPA is working to freeze those rules so that the fleet average would peak at about 37 miles per gallon by 2025 instead.

Trump officials say the Obama-California rules will reduce safety and increase the price of vehicles. California officials say the safety argument is not supported by science and that the state’s rules reduce costs over the life of vehicles due to the need for motorists to buy less gasoline.

Wheeler told the auto dealers Tuesday that the administration will not revoke California’s ability to reduce smog, soot and other types of air pollution from vehicles, only its rules on greenhouse gas.

“One national standard will provide much-needed regulatory certainty to automakers, dealers and consumers,” he said.

Ironically, much of the issue may be blunted by the fact that in July, four large automakers — Ford, Volkswagen, BMW, and Honda — signed a voluntary agreement with California to largely follow the state’s standards regardless of whether the Trump administration granted or approved the waiver.

Auto analysts said the companies wanted a deal so they could have certainty for their assembly lines, rather than being whipsawed by court decisions and a possible new president in 2021. Also, other countries, particularly in Europe, already require the tougher standards for all vehicles sold there.

But the news of the compromise sent Trump into a rage.

“Crazy!” the president tweeted in July. “The Founders of Ford Motor Company and General Motors, are ‘rolling over’ at the weakness of current car company executives.”

Earlier this month, the Wall Street Journal reported that the Department of Justice has opened an anti-trust investigation into the four companies over the issue.

Transportation accounts for 41 percent of California’s greenhouse gas emissions. Although the state has made considerable progress toward its goals — hitting a target of 33 percent of its electricity generated by solar, wind and other renewable power, for example — it cannot reach its 2030 climate goals without significant reductions in emissions from passenger cars, light trucks and SUVs.

Environmental groups came to California’s defense Tuesday.

“The existing standards will save drivers money at the pump, cut hazardous air pollution and help us address climate change,” said Luke Tonachel, director for clean vehicles and fuels at the Natural Resources Defense Council.

“Pretending that automakers cannot make cars that are both safe and efficient is ridiculous, and the American people are not falling for it,” he added. “Cleaner, more efficient cars are cheaper to own because the fuel savings dwarf any initial expense.”