The Trump administration Wednesday revoked California’s federal waiver on emissions, moving to reduce the influence of the nation’s most populous state on the auto industry and clean air standards.

The move is the second in recent weeks to prevent California from imposing stricter emissions standards than those mandated by the federal government. Earlier the Justice Department announced it is investigating whether four automakers broke antitrust rules by signing on to the stricter standards.

In a series of tweets, Trump said revoking California’s waiver will help make cars and light trucks less expensive, enabling automakers to include more safety equipment. He said it’s actually a win-win because cars will not only be safer, but older, more polluting vehicles will be taken off the road as Americans can afford newer vehicles.

California Gov. Gavin Newsom vowed legal action against the administration and predicted, “California will prevail because we’re leaders in this space.”

Newsom called Trump’s action “political theater” and “a failed attempt to assert power.” He also accused the president of conducting a vendetta against the state.

Newsom predicted federal standards will cost consumers $400 billion, lead to the consumption of an additional 320 billion gallons of oil and hurt automakers’ ability to compete in the global market.

Trump said there’s little difference between California and U.S. emissions standards.

“Many more cars will be produced under the new and uniform standard, meaning JOBS, JOBS, JOBS!” the president tweeted. “Automakers should seize this opportunity because without this alternative to California, you will be out of business.”

A study published in the journal Science took issue with Trump’s safety claims, saying there are “fundamental flaws” in the administration’s analysis.

Seventeen automakers have urged California and the White House to work together on a single national standard, warning the uncertainty is putting jobs at risk.

The administration said it was rolling back emissions rules to give the public greater access to more affordable vehicles. Transportation Secretary Elaine Chao said there are “compelling reasons” for the revisions, which she characterized as “more realistic.”

The administration said the revisions would save society more than $500 billion. The Obama administration had sought to require average vehicle fuel economy of 46.7 mpg by 2026. The Trump administration revisions would reduce that figure to 37 mph.