WASHINGTON — A federal appeals court in San Francisco on Wednesday upheld a block on President Trump’s attempt to use $2.5 billion from the Department of Defense to construct a wall along the southwestern border, impeding the delivery of one of his signature campaign promises.

The divided three-judge panel in the Ninth Circuit agreed with a lower court’s decision from Friday that ruled the Trump administration did not have the authority to reallocate the funds without congressional approval. The administration immediately appealed.

Two of the three judges on the panel affirmed that the administration could not build the barriers during future challenges.

“We conclude that it is best served by respecting the Constitution’s assignment of the power of the purse to Congress, and by deferring to Congress’s understanding of the public interest as reflected in its repeated denial of more funding for border barrier construction,” wrote Judges Michelle Friedland, an Obama appointee, and Richard Clifton, a George W. Bush appointee.