A U.S. judge on Monday blocked plans to move the FBI’s headquarters to a federal office building in Washington, finding that President Donald Trump’s administration illegally tossed out a previously approved plan to build a new facility nearby in Maryland.

The ruling is the latest development in a yearslong battle over where to house the main office for the nation’s premier law enforcement agency. A site in Greenbelt, Maryland, was picked during former President Joe Biden’s administration, but Trump appointees sought to reverse that decision last year in favor of repurposing the Ronald Reagan Building, a federal office complex a few blocks from the FBI’s existing headquarters.

U.S. District Judge Theodore D. Chuang, an appointee of President Barack Obama, ruled that the move was “ not in accordance with law,” and blocked the Trump administration from moving the FBI to the Reagan building, renovating it for the FBI or repurposing funds.

“This is not the first time courts have tried to undermine the administration in its goal to make government more cost-effective for American taxpayers,” the FBI said in a statement. “The court has chosen to impermissibly intervene for political reasons. This FBI is mission focused and will continue the best course of action to meet the needs of law enforcement.”

The suit was brought by the state of Maryland and Prince George’s County.

“Maryland and Prince George’s County committed more than a decade of work to earn the FBI headquarters and pledged hundreds of millions of dollars,” Maryland Attorney General Anthony Brown, a Democrat, said in a statement. “By blocking the Trump Administration’s unlawful attempt to move the FBI to the Reagan Building and divert the funds Congress set aside for this project, the Court has cleared the path back to Greenbelt.”

Maryland Gov. Wes Moore, also a Democrat, said, “Now it is time to stop the games and get to work building the world-class FBI headquarters that our public servants deserve, where it belongs: in Prince George’s County, Maryland.”

The FBI’s current Pennsylvania Avenue headquarters, the J. Edgar Hoover Building, was dedicated in 1975. Proponents of moving the headquarters have said the brutalist-style building, where nets surround the facility to protect pedestrians from falling debris, has fallen into disrepair.

The Maryland location was selected over nearby Virginia following an intense competition between the two states.