Transcript for Trump says Kim Jong Un 'promised me he wouldn't be testing' nuclear weapons: Part 4
house is restricted virtually every day. Unless it's a day when you've inked a deal to sell fighter planes to Poland. Moments ago, we witnessed that impressive flyover of this cutting-edge f-35 as it flew over the white house. Today's showmanship, just the latest demonstration of the president's "Out of the box" approach to foreign policy. Case in point, the unusually warm relationship he's struck up with north Korean dictator Kim Jong-un. I just received a beautiful letter from Kim Jong-un, and I think the relationship is very well but I appreciated the letter. After a day filled with photo ops, pressers, and back-to-back meetings, including one on the opioid crisis with the first lady Melania trump -- And I will continue to bring the awareness how dangerous drugs are. It's finally time for our sitdown interview with the president. At 4:34 P.M., on the patio just off the rose garden. One year ago today, we were in Singapore right after your meeting with Kim Jong-un. And you told me then that you trust him. And you also put out that tweet. "There's no longer a nuclear threat from North Korea." But there is a nuclear threat today, isn't there? Well, it could change. I would say not much. There's been no testing, no anything. But it could change. And there's been no nuclear testing except for very short range. And that's something that a lot of nations test, frankly, what he tested. I think we've made tremendous progress. Now, I will let you know if it goes the other way. And it can, and it can happen instantly. But we've done a very good job. Do you think he's still building nuclear weapons? I don't know. I hope not. He promised me he wouldn't be. He promised me he wouldn't be testing. So you still trust him? Well, look, I couldn't tell you that. It would be very insulting to him. But the answer is, yeah, I believe that he would like to do something. I believe he respects me. I get along with him really well, I think I understand him, and I think he understands me. But there have been these cycles, as you know, with the family, with North Korea, with president Clinton, with president George W. Bush. And everybody gave him a lot. President Clinton gave him billions and billions of dollars and got nothing. I've given nothing. Now, at some point -- But do you worry that he could be playing you, too? Well, look, I put on sanctions. The sanctions are on. We've gotten our hostages back. We've gotten the remains. And they continue to come back, the remains of our great heroes from the past. I asked the president about the return of one American in particular. College student Otto Warmbier who came back from North Korea in a comatose state and later died. Brazenly, the north Koreans reportedly billed the united States $2 million for Warmbier's medical care. Did they try to make you pay for Otto Warmbier? When you say "Me," -- The United States. Because I didn't know him at that time. That was a very different deal. But here's the bottom line. I ended it. We didn't pay. We never paid. What he did with other people in the state department, that's irrelevant. And I have great respect for Otto's parents. And what happened to Otto is horrible, horrible. But we never paid for Otto. The president says he's willing to deal personally with Kim Jong-un despite his horrific record on human rights. Kim has executed many in the north Korean elite, including, reportedly, members of his own negotiating team after the last failed summit. It appears that meeting with you is dangerous for members of his negotiating team. Somebody said, "Well, I guess he's a tougher negotiator maybe than we thought." The fact is that I don't know what happened with the five people. I have no idea whether or not anything happened to anybody else. You know, you hear all sorts of stories, but I don't know that -- What -- -- They're true. And you would never know and probably wouldn't be able to find out very easily. It's not easy. It's a closed society. Lift a veil on your strategy here. You know, I listen to you every single day. All Americans do. Especially over these last couple days. You know, you -- "The press are enemy of the people. Fake news. Joe Biden's a loser, low iq." Yet all these warm words -- And other people are very good. -- For Kim Jong -- no, but explain the strategy -- I say nice things about you. Maybe you're in that category. You never know. But there seems to be a dissonance there. I don't think so. I say a lot of nice things about a lot of people that are very soft and nice. And I say good things about lots of people. Look, I'm in charge of a very, very special gift. It's this incredible country. I'm dealing with people. Some might be nice, and some might not be nice. But I've done a great job.
This transcript has been automatically generated and may not be 100% accurate.