Transcript for North Korea, South Korea agree to end war

We, of course, begin with breaking news overseas. A remarkable summit viewed live around the globe. The leaders of north and south Korea meeting. Kim Jong-un, the first leader of his nation to enter the south. Will this lead to peace? ABC's chief foreign correspondent Terry Moran is in the region and has the latest. Good morning, Terry. Reporter: Good morning, robin. Good evening here. What an extraordinary day. Thousands of around the world here just south of the demilitarized zone to witness this historic and emotional summit. Just weeks ago this whole region seemed under the looming threat of war, but these two men, the leaders of the two Koreas, in striking symbolism and long talks are trying to bring in Kim Jong-un's words a new era of peace. Surrounded by bodyguard, Kim Jong-un emerged from the northern side of the dmz, then looking a bit tense he strode alone toward the cease-fire line from the Korean war that still marks the border here. A warm handshake with south Korean president moon jae-in and then Kim steps forward becoming the first north Korean leader in history to set foot on south Korean territory. President moon asked you come to the south. When can I come to the north? Why don't you try now, Kim Jong-un says and hand in hand they cross back, almost as if turning that fearsome border into just a simple line. It was like that all day, symbolism and ceremony. Greeting children who live in the dmz. They're the future. ?????? a traditional honor guard, the shared Korean culture but there was laughter also. Kim Jong-un cracking a grim joke as the two began their meetings, I won't interrupt your sleep anymore with early morning missile tests, he promised. The two men so different seem to enjoy it all sitting among the trees alone for almost 45 minutes introducing their wives, Kim Jong-un's wife all smiles. And they reached a remarkable joint agreement, signed and then celebrated with a handshake triumphantly raised arms and unexpected bear hug. Afterwards Kim Jong-un addressing a world audience for the first time. Saying, we are one nation and cannot be separated. We are one blood. And in that symbolism there was substance as well. In that joint agreement, the two men declared that by the end of this year they will reach a peace treaty bringing a formal end to the Korean war. They will denuclearize the Korean peninsula and increase economic ties but the key question as it always has been, can North Korea be trusted? George. Right, can they follow through on getting rid of their nuclear weapons. That is going to be a huge question. President trump up and tweeting this morning, praising the progress, praising the meeting saying good things are happening but only time will tell. That also gets to the question of what this all means for the potential upcoming summit between Kim Jong-un and president trump. Reporter: Well, George, this summit between the Korean leaders was seen as kind of the laying the table for the big deal, the summit between president trump and Kim Jong-un. And there's no question president trump will want to hear from president moon of South Korea. What he made of Kim Jong-un as a negotiator. Right now, it looks like it's all systems go and that summit scheduled tentatively, no date yet late may, early June. Yeah, and, in fact, "The new York Times" is reporting this morning it's June and likely to be Singapore. Do we know anything more about the various cities and regions in play? Reporter: Well, that turned out the location turned out to be a really delicate negotiation in part because Kim Jong-un's airplanes are so old they have a limited range so they had to do something within a couple thousand miles. Singapore fits the bill. The Americans like it. Didn't want to do it in the Koreas because one side or the other would look subservient. Didn't want to do it in China so Singapore looks like it might well be it. Terry Moran, thanks very much.

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