Transcript for North Korea and China confirming reports of meeting in Beijing

Next tonight here, north Korea and China now confirming those reports of that mysterious mating in beijing. Kim Jong-un did, in fact, go. It was his first diplomatic appearance on the world stage, welcomed by China's president XI, before that face-to-face planned with president trump. Here's ABC's chief global affairs correspondent Martha Raddatz tonight. Reporter: The clues were all there. The secrecy. That deep green armored train spotted in beijing. The heavy security for the convoy that was there on arrival. But the mystery is now over. Kim Jong-un had journeyed outside North Korea for the first time since taking power. His wife at his side. Chinese president XI pulling out all the stops. A review of the troops. Toasts between the two leaders and a banquet. The Chinese, who released images of Kim taking notes as president XI spoke, say that Kim told them, "The issue of denuclear za Zack of the Korean peninsula can be solved, if south Cree beyond a the United States respond to our efforts with goodwill." We're going to be cautiously optimistic, but we feel like things are moving in the right direction. Reporter: Kim's secret trip took even the white house by surprise. President trump preparing for his own meeting with the north Korean leader, raising expectations today with a tweet. "Everyone said that peace and the denuclearization of the Korean peninsula was not even a small possibility. Now, there is a good chance that Kim Jong-un will do what is right for his people and for humanity." His incoming national security adviser, John Bolton, was one of those voices of gloom. There's an all-purpose joke here. Question. How do you know that the north Korean regime is lying? Answer. Their lips are moving. Martha Raddatz live with us from Washington tonight. And Martha, John Bolton sounding at least publicly a lot more skeptical than the president right now. Bolton saying he wants this meeting to happen sooner rather than later? Reporter: That's right, David. He says he hopes the meeting can be even sooner than may, because he doesn't want the north Koreans to stall us, while continuing with their nuclear weapons program. So, the sooner, the better, to see if they are sincere. David? All right, Martha Raddatz, always good have you.

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