Transcript for Trump: 'Nothing has changed on North Korea that we know of'

tonight, president trump answering questions about north Korea. Will there be a sum milt after all? The president answering reporters, but seeming to speak directly to Kim Jong-un today, offering him protection now if he agrees to a deal. It comes after North Korea threatened to cancel the summit, and ABC's senior white house correspondent Cecilia Vega at the white house tonight. Reporter: Will there or won't there be a summit with north Korea? Today, president trump said he's in the dark, just like everyone else. Well, nothing has changed on North Korea that we know of. We have not been told anything. We're just raegd stories like you are. Reporter: But tonight, for this art of the deal president, his biggest deal yet is at risk of falling apart. That's what I do, is deals. And with deals, you have to have two parties who want to do it. He absolutely wanted to do it. Reporter: So what went wrong? President trump blames Kim's recent trip to China. There has been a big difference since they had the second meeting with president XI. President XI could be influencing Kim Jong-un. But we'll see. Reporter: But Pyongyang says it is livid that national security adviser John Bolton, who they once referred to as human scum, called on them to do what Libya did more than a decade ago. We have very much in mind the Libya model from 2003, 2004. Reporter: To North Korea, that sounds like regime change. After Libya gave up its nuclear program, dictator moammar Gadhafi was overthrown and in the streets. Today, with Bolton right there looking on, president trump flatly contradicted him. Well, the Libyan model isn't a model that we have at all when we're thinking of North Korea. This would be with Kim Jong-un, something where he'd be there, he'd be in his country, he'd be running his country. His country would be very rich. Reporter: And then, he sent a reassuring message directly to Kim himself. He'll get protections that will be very strong. If we make a deal, I think Kim Jong-un is going to be very, very happy. I really believe he's going to be very happy. Reporter: And from a prest who beamed at talk of the ne bell Nobel peace prize -- Nobel! Nobel! Nobel! That's very nice, thank you. That's very nice. Nobel. Reporter: Today, a different tone. Look, I want to have peace in the world. That's what I really want. More so than the Nobel peace prize or any other prize. Cecilia Vega with us live again tonight from the white house. And Cecilia, as those negotiations continue with north Korea, the president's lawyers negotiating something else, this possible interview with Robert Mueller and the Mueller investigation. This was news, Rudy Giuliani saying that Robert Mueller's team has assured them that the president will notindicted. If that's true, how significant would that be? Reporter: Justice department lawyers have long said they do not have the authority to indict a sitting president, but Robert Mueller can actually issue a report on his findings, that could trigger impeachment proceedings in congress. He could name president trump as an unindicted coconspirator, but we have no idea what Robert Mueller is going to do, because he's not commenting publicly on this one. Rudy Giuliani is interpreting this as a big win. All right, Cecilia Vega with us again tonight. Cecilia, thank you. From Connecticut tonight, a police officer is fighting for

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