The Trump administration has dropped an antitrust investigation into four car companies that negotiated with California to raise the fuel economy of their new vehicles above national standards.

Representatives of two of the companies, Ford and BMW of North America, confirmed Friday that the Justice Department had closed its investigation. The other two companies, Honda and Volkswagen, declined to comment on the status of the inquiry. The New York Times reported that the department ended its probe after determining that none of the automakers had violated federal law.

Gov. Gavin Newsom announced the deal with the car companies last summer, circumventing the federal government’s efforts to roll back fuel-efficiency targets that had been set under former President Barack Obama.

California’s battle with the federal government over car pollution is not over, however. In September, the Trump administration revoked the long-standing waiver that gave the state authority to set its own emissions standards for vehicles, an action that California and 22 other states are fighting in court.

The Justice Department did not respond Friday to a request for comment about the status of its antitrust investigation.

Newsom celebrated the end of the probe as “a big loss for the president and his weaponization of federal agencies — and a victory for anyone who cares about the rule of law and clean air.”

“These trumped-up charges were always a sham — a blatant attempt by the Trump administration to prevent more automakers from joining California and agreeing to stronger emissions standards,” he said in a statement.

As the automobile industry sought relief from increasing standards, President Trump moved in 2018 to block the Obama administration’s fuel mileage targets for 2021 through 2025.

Under Trump’s proposal, fuel economy would continue to increase to roughly 37 miles per gallon in 2020, but it would stop there, well short of the currently planned 47 mpg in 2025. Administration officials contend that tougher emissions targets raise the price of manufacturing vehicles, keeping older, more dangerous cars and trucks on the road and leading to more traffic deaths.

But California, and more than a dozen other states that follow its lead on reducing emissions of climate-changing greenhouse gases, sued to stop the plan and vowed to stick by their own stricter standards for vehicles. That raised concerns in the industry that the national automobile market could be cleaved in two and brought some companies, seeking stability, to the negotiation table with California.

Newsom and the California Air Resources Board announced an agreement in July with Ford, Honda, VW and BMW, which represent about 30% of U.S. car sales. The companies promised to reduce greenhouse gas emissions from their vehicle fleets by almost 4% annually for five years, bringing their overall mileage to roughly 50 miles per gallon by model year 2026.

The governor said at the time that raising fuel efficiency for vehicles, which are the single largest source of greenhouse gas emissions, was the most important step California could take to reach its ambitious goals to combat climate change. He later said two more companies, including Mercedes-Benz, were close to joining the compact, though that deal has not materialized.

The Justice Department opened its antitrust probe into the automakers in September, the first of several steps it took to crack down on California’s climate agenda. In addition to revoking the emissions waiver, the Trump administration also sued the state over its cap-and-trade agreement with the Canadian province of Quebec and threatened to freeze federal highway funds over alleged violations of federal clean air standards.

Alexei Koseff is a San Francisco Chronicle staff writer. Email: alexei.koseff@sfchronicle.com Twitter: @akoseff