The U.S. Transportation Department said in a letter Tuesday that it plans to cancel about $929 million in federal grant money for California’s high-speed rail project and announced that it would seek a return of $2.5 billion in funds that were already allocated for the project, spurring accusations of political retaliation from the state’s Democratic governor, Gavin Newsom.

Last week, Newsom said he planned to scale back plans for the rail project, which would have linked Los Angeles to San Francisco. In his State of the State address, Newsom declared that the originally proposed rail project was too expensive for the state and that California would instead use the federal funds to complete a shorter segment of the rail through the Central Valley.

President Trump has taken aim at the rail line before, saying last week after Newsom announced his plans to scale back the project that California had already “wasted many billions of dollars” on it.

“We want that money back now,” the president wrote Feb. 13. “Whole project is a ‘green’ disaster!”

On Wednesday morning, he again discussed the rail line, on Twitter.

Trump’s point is echoed in the Transportation Department’s letter to the California High-Speed Rail Authority. It said the state had failed to make “reasonable progress” on the rail project, which voters approved in 2008 and had a previously agreed-upon deadline of 2022. In a statement, the department said it would be “exploring every legal option to seek the return from California of $2.5 billion in federal funds.”

In a tweet early Tuesday, Trump asserted the failed project had record-setting costs “hundreds of times more expensive” than his proposed U.S.-Mexico border wall. The tweet came one day after a coalition of 16 states, including California, filed a federal lawsuit against the Trump administration, claiming its move to declare a national emergency for the border wall was unconstitutional.

Newsom alluded to Trump’s tweet in a statement Tuesday and suggested the move was retaliation. “It’s no coincidence that the Administration’s threat comes 24 hours after California led 16 states in challenging the President’s farcical ‘national emergency.’ This is clear political retribution by President Trump, and we won’t sit idly by. This is California’s money, and we are going to fight for it,” Newsom wrote.

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