On Thursday, the administration sent an email to members of Congress saying appeals by two companies identified as WNIS and Penna Group delayed construction to early November, with completion scheduled for early December. The Government Accountability Office has dismissed WNIS' protest but is still evaluating the protest lodged by Parra Group. The border protection agency has said it should be impossible for people to climb it on their own and that it should be impenetrable to sledgehammers and battery-operated tools trying to damage it for a full hour. Building a wall on the Mexican border was a cornerstone of Trump's presidential campaign and a flashpoint for his detractors.