A three-judge federal appeals panel has allowed construction on President Trump's White House ballroom to continue into June, despite a federal judge limiting the project to "below-ground construction". The panel granted the Trump administration a stay of U.S. District Judge Richard Leon's order from Thursday. The $400 million project will be made with missile-resistant steel columns, drone-proof roofing materials, and will also house top-secret military installations, medical facilities and bomb shelters. The Department of Justice has appealed the ruling, suggesting it could jeopardise national security and the White House.