"One of the main reasons North Korean athletes don't defect is due to their families back in North Korea", Benjamin Young, a doctoral candidate at George Washington University who has researched sports in North Korea, told ABC News' Mae Joo.
Moon and the delegates agreed to maintain the conciliatory mood inspired by the Olympics and promote inter-Korea dialogue and cooperation, the presidential office said.
A visit by Moon to the North would be only the third inter-Korean summit to take place.
Aides did not immediately say whether the invitation was discussed as the two sat next to each other viewing several race heats Saturday.
A DPRK taekwondo demonstration team has also come to demonstrate the traditional Korean martial art during the Winter Olympics.
The warm reception was at odds with the position taken by U.S. vice-president Mike Pence.
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Manchester City extended their lead atop the Premier League table to 16 points with a convincing 4-1 win over Leicester City . The former Athletico Madrid Fox in the box, restored the lead for the Citizens less than five minutes after recess.
US Vice President Mike Pence also attended the Games opening ceremony but had no contact with the North Korean delegation.
"The Vice President is grateful that President Moon reaffirmed his strong commitment to the global maximum pressure campaign and for his support for continued sanctions", press secretary Alyssa Farah said. The overture follows heightened tensions over the North's missile tests.
The president responded by saying that the two sides should work on establishing the right conditions to realise the meeting, according to the spokesman.
Pence said the United States and South Korea were closely aligned in their approach to dealing with North Korea.
"As an athlete myself it was a great honour for me to be the last torch bearer", she said.
Even Japanese Prime Minister Shinzo Abe, who has shared the American skepticism of warming North-South relations and pressed Moon against falling for the North's "smile diplomacy", greeted Kim Yong Nam.
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But the teen had no idea that Timberlake would be coming through his section. McKenna made his way down to Timberlake a few rows down.
The discussions from Saturday's meeting weren't immediately released.
South and North Koreans marched together under a unified flag at the games' opening ceremony. Instead of 23 players she would have an unwieldy 35 with the addition of a dozen North Koreans, three of whom had to dress for every game.
The officials toasted with the Korean liquor "soju" and were served buckwheat and potato pancakes, dried pollock soup, grilled halibut and other dishes.
North Korean cheerleaders let rip in support for Choe Un Song but he was eliminated in the heats for the 1,500m short-track speed skating, failing to reach the semi-finals. "VP stands and cheers for USA athletes, VP hangs out with US athletes instead of dining with Kim regime, VP does not applaud N. Korea or exchange pleasantries w/ the most oppressive regime on earth", Agen tweeted, with check marks next to each item.
The first hockey match featuring the joint North-South women's ice hockey will be held Saturday night - they play Switzerland, where both Kim Jong Un and his sister went to school when they were children - and that would be an event she might want to see.
Her exact role in the regime is unclear, but her job is similar to a chief of staff and she regularly reviews the statements and speeches issued by her brother. As a sign of her status, the elder Kim Yong Nam offered her the seat of honor at the airport meeting, but she politely declined.
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With two rocks on the red zone of the target to start the ninth end, Finland was in prime position to get a much-needed win. Korea led the game 2-1 through three before OAR regained the lead with two in the fourth and one more in the fifth.