Transcript for President Donald Trump and Kim Jong Un arrived in Singapore for historic summit

night early because president trump and Kim Jong-un have landed here in Singapore. This has not happened before with a sitting U.S. President. The stakes are enormous. Kim Jong-un arriving with his entourage of aides and body guards. President trump arriving a few hours later. Their hotels a few miles apart. This has been a roller coaster for the world to witness. And for the world to witness. Kim Jong-un and his missile tests. President trump threatening fire and fury calling Kim Jong-un little rocket man. In a little more than 24 hours they'll meet face-to-face. ABC's chief white house correspondent here in Singapore leading us off. Reporter: President trump says he's been preparing for this moment his whole life. As he landed in Singapore, he sounded confident. How are you feeling about the summit? Is it going to be a sucss? Very good. Thank you. Very good. Reporter: Five hours earlier, an air China jet touched down here, carrying Kim Jong-un. It's only the third time the north Korean leader has traveled outside his isolated country since taking power. Traveling with him, his sister, who has assumed a more prominent role in the run-up to the summit on the streets of Singapore hundreds turned out to watch the north Korean motorcade drive by. Kim's personal bodyguards running alongside his limousine. Later, the reclusive dictator thanked Singapore's prime minister for his "Sincere efforts" for the summit. If the summit proves successful, Kim declared, the name of Singapore will go down in history. The eyes of the world now are on the 36-year old dictator. His new shift to diplomacy comes after a year of escalating provocations. He has tested a hydrogen bomb and more missiles than both his father and grandfather combined, including at least one capable of reaching the United States. Rocket man is on a suicide mission for himself and for his regime. Reporter: The threats and the name calling have gone both ways. Kim has called trump a "Mentally deranged dotard" and "An old lunatic." Trump has called Kim a "Maniac," a "Madman" and a "Sick puppy." They will be met with fire and fury like the world has never seen. Reporter: But now, president trump calls the summit a "One time shot" to make peace. I feel that Kim Jong-un wants to do something great for his people and he has that opportunity and he won't have that opportunity again. It will never be there again. Reporter: He says he'll know immediately if Kim is serious. How long will it take? I think within the first minute I'll know. Reporter: How? Just my touch, my feel, that's what I do. I think I'll know pretty quickly whether or not something positive will happen. And if I think it won't happen I'm not going to waste my time, I don't want to waste his time. Jon Karl joins us live in Singapore tonight. Jon, we heard the president say he'll know in one minute if Kim Jong-un is serious about denuclearization. We've been listening to the president in recent days he's tried to lower expectations somewhat, describing the summit as just the first step. He's done both. He's raised expectations and lowered expectations. He's called it the one shot for peace and a first step. This firsthand shake between esident trump and Kim Jong-un will be a carefully choreographed event, the two men coming together before the cameras. They'll have two meetings. The first one a very small group of people, the president, Kim Jong-un, their translators and at the very most one more on the American side, secretary Pompeo. David. We know their every step will be planned. Jon Karl leading us off. Thank you.

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