Trump Gives a br Deadline to Close br the USMexico Border President Donald Trump br repeated his threat to shut br the Southern U.S. Border in br a series of tweets on Friday. The Justice Department declined br to comment on whether or not br Trump could legally close the border. Customs and Border Protection br Commissioner Kevin McAleenan br described the situation with the U.S. br immigration system as "at the breaking point." Department of Homeland br Security Secretary Kirstjen Nielsen br said the influx of migrants at the br border is a "cascading crisis." In an series of tweets br from December of last year, br the President threatened br to close "the whole border.