Transcript for Trump on North Korea summit: 'There is a chance it will work out'

following all day long here, the new message from president trump when it comes to that face to face summit with Kim Jong-un. The summit appears to be on shaky ground tonight. President trump himself casting some doubt today during an urgent meeting at the white house with South Korea's president. The president saying the plans are still moving forward, but the president also indicating that he believes something changed when the north Korean dictator traveled to China to meet with president XI. ABC's chief white house correspondent Jonathan Karl on the new promises president trump is now making to try to make this happen. Reporter: President trump today greeted South Korea's president, leading him by hand into the west wing to huddle about the summit with Kim Jong-un. A summit the president now says may or may not happen. There is a chance it will work out. There's a very substantial chance that it won't work out. And that's okay. That doesn't mean it won't work out over a period of time. But it may not work out for June 12th. Reporter: It was the north Koreans who first raised the possibility of canceling, objecting to demands from the U.S. They give up their entire nuclear program before getting anything in return. Today, the president suggested he could back down from insisting Kim gives up all his nukes at once. It would certainly be better if it were all in one. Does it have to be, I don't think I want to totally commit myself, but all in one would be a lot better. Seemed to blame China for the Reporter: President trump seemed to blame China for the complications, saying Kim Jong-un changed his tune after having a second, unannounced, meeting with the Chinese president. I think there was a little change in attitude from Kim Jong-un. So, didn't like that. I don't like that. Reporter: President trump made it clear he's willing to offer a lot to the north Korean dictator. I will guarantee his safety. Yes. He will be safe. He will be happy. His country will be rich. Reporter: He says Japan, China and South Korea will pitch in, too. They will be willing to help and I believe invest very, very large sums of money into helping to make North Korea great. Reporter: The president has relished talk of the summit as a path to the Nobel prize. That's very nice, thank you. That's very nice. Nobel. Reporter: A military office assigned to the white house has already created a commemorative coin for the summit, referring to Kim as, quote, supreme leader. Supreme leader. Jon Karl from the white house tonight. And Jon, the president once said that when it came to North Korea and the summit, it was very simple, in the president's words, saying North Korea would have to, quote, get rid of their nukes before any benefits from a deal. Today, he seemed to move the goal posts a bit. Reporter: Well, the president said today he would still like to have what he called an all in one deal, but he certainly left open the possibility of accepting something short of that, and David, make no mistake, rewarding North Korea before it gives up its entire nuclear program would be a major concession. All right, Jon Karl live from the white house again tonight. Thanks, Jon.

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