Transcript for Trump warns North Korea 'not to underestimate us'

Next this morning on this first anniversary of president trump's stunning election victory it's the Democrats who are celebrating now. Big victories last night in the Virginia and New Jersey races for governor. With exit polls showing voters wanted to send a message to president trump. This as Republicans are under pressure to pass their tax bill quickly amid questions about its cost whether it benefits the middle class most. The president called into a meeting of senate Democrats to get their support. The president delivered a forceful address on North Korea holding open the prospect of talks warning do not underestimate us and do not try us. Our senior white house correspondent Cecilia Vega is in beijing with the president. Good morning, Cecilia. Reporter: Hey, George, good morning to you. President trump needs China to help put the pressure on north Korea. This is a visit that requires skilled diplomacy and it is one that is being called his most crucial trip -- crucial stop of this entire trip. ??? this morning, president trump touching down in China. The country often uses as a political punching bag rolling the stairs it right up to air force one and rolling out the red carpet. President XI jinping playing tour guide taking them to the forbidden city and to a traditional Chinese opera. That's something. We're having a great time. Thank you. Reporter: The high-stakes visit perhaps president trump's most important stop yet as he pushes China to ramp up the pressure on North Korea. Before leaving Seoul, the president delivered a message directly to Kim Jong-un. The weapons you are acquiring are not making you safer, they are putting your regime in grave danger. Every step you take down this dark path increases the peril you face. Reporter: But he had a message for China and Russia too. All responsible nations must join forces to isolate the brutal regime of North Korea and to those nations that choose to ignore this threat or worse still to enable it, the weight of this crisis is on your conscience. Reporter: And he had this warning. Today I hope I speak not only for our countries but for all civilized nations when I say to the north do not underestimate us and do not try us. Reporter: A stern warning there. Now despite white house aides repeatedly insisting the president would not take a trip to the dmz the demilitary terrorized zone, that border between north and South Korea during the trip before he left Seoul he boarded marine one and headed for the dmz but the white house says he had to cut that short, turn around about five minutes before landing there blaming bad weather, robin. Okay, Cecilia, thank you very much.

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