Transcript for Trump threatens to close entire southern border over wall

custody, he was placed into corporal Singh's handcuffs. Thank you. And president trump's new ultimatum, threatening the close the southern border unless he receives funding for the wall. In a trip kept under wraps, secretary Neilsen traveling to the border. Here's Tara Palmeri. Reporter: Tonight, president trump raising the stakes in the battle over the border. Tweeting, "We will be forced to close the southern border entirely if the obstructionist Democrats do not give us the money to finish the wall." Incoming acting chief of staff Mick Mulvaney saying Democrats should take the president's threat seriously. All options are on the table. Listen, it's the only way to get the Democrats' attention. There's not a single Democrat talking to the president of the United States about this deal. Reporter: But democratic leader Nancy Pelosi says Democrats won't fund the president's, quote, "Immoral, ineffective and expensive wall." President trump also threatening to cut aid to three central American countries, tweeting, quote, "Honduras, Guatemala and El Salvador are doing nothing" about the surge of migrants. While Washington is deadlocked, in border cities like El Paso, Texas, there is a growing crisis. Just this week, a migrant child detained there later died, the second child to die in U.S. Custody this month. And now, more than 1,600 migrants have been released from facilities there that officials say are overcrowded. Homeland security secretary kirstjen Nielsen on the ground in El Paso today, touring some of those immigration facilities, visits that were closed to the press. Tara, the president is not backing down. The Democrats are not giving in. Reporter: Tom, there is still no deal on the table. In fact, neither side is even speaking to each other at this point. Meantime, 42,000 active duty coast guard members will not be paid. Museums will close, and hundreds of thousands of federal workers

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