WASHINGTON — A federal judge has blocked the Trump administration from moving the FBI headquarters to the Ronald Reagan Building in downtown Washington, creating a new legal setback over the future location of the nation's main federal law-enforcement headquarters.

U.S. District Judge Theodore D. Chuang ruled that the administration's decision to abandon a previously approved site in Greenbelt, Maryland, was not lawful. The ruling also prevents the administration from proceeding with plans to renovate the Washington building for FBI use.

The headquarters dispute has been developing for years. The FBI's existing J. Edgar Hoover Building in Washington has long faced criticism over its aging infrastructure, while officials have debated whether to construct a new campus outside the capital or renovate an existing federal building.

The Trump administration had moved toward the Ronald Reagan Building option after reversing the previous administration's decision to develop the Maryland site.

The latest ruling could force federal officials to reconsider their relocation strategy and potentially lead to further litigation.

The dispute also highlights the broader political debate over federal spending, government property and the future structure of the FBI.

The court decision adds another major complication to the administration's effort to reshape the FBI's headquarters while the agency continues operating from its aging Washington facility.