South Korea's leader invited to North Korea

North Korea has invited South Korea's President Moon Jae-in to visit Pyongyang. If he and North Korea's Kim Jong-un do meet it would be the first summit between Korean leaders in more than a decade.

Kim Jong-un sends written invitation through sister, who is representing North Korea at Olympics

South Korean President Moon Jae-in had quite a day on Saturday, lunching with the North Korean delegation and getting an invite to visit North Korea, and then hosting U.S. Vice-President Mike Pence at the short track speed skating in the evening. (Susan Ormiston/CBC)

A rare invitation to Pyongyang for South Korea's president marked Day Two of the North Korean Kim dynasty's southern road tour Saturday, part of an accelerating diplomatic thaw that included some Korean liquor over lunch and the shared joy of watching a "unified" Korea team play hockey at the Olympics.

Nothing has been settled on any trip north by South Korean President Moon Jae-in. But the verbal message to come at a "convenient time" from dictator Kim Jong-un, delivered by his visiting little sister, Kim Yo-jong, is part of a sudden rush of improving feelings between the rivals during the Pyeongchang Olympics. The result: a heady, sometimes surreal, state of affairs in a South Korea that has seen far more threat than charm out of the North.

South Korea has dubbed them Kim Jong-un's 'army of beauties,' a squad consisting of more than 200 women who were chosen to lift the spirits of their country's Olympic athletes 0:35

Still, it wouldn't be South Korea if people weren't asking the perennial question when it comes to North Korea changing gears and showering its rival with apparent affection: What's in it for Pyongyang?

Past "charm offensives" have been interpreted as North Korea trying to recoup from crippling sanctions on their nuclear program, or trying to drive a wedge between Seoul and its U.S. ally.

Soldiers march during a grand military parade on Thursday celebrating the 70th founding anniversary of the Korean People's Army. (KCNA via Reuters)

A massive military parade in Pyongyang on the eve of the just-opened Pyeongchang Games has been used as Exhibit A by skeptics. In it, Kim Jong-un highlighted several huge intercontinental ballistic missiles, which were successfully flight tested three times last year and could reach deep into the U.S. mainland when perfected.

Even so, there's also cautious optimism, or curiosity at least. If peace isn't imminent, a summit in Pyongyang between Moon and Kim Jong-un seems preferable to recent months' threats.

Moon told Kim Yo-jong that the North and South should continue to build conditions for a summit, Moon spokesman Kim Eui-kyeom said Saturday. The U.S. and the North should quickly resume dialogue, he said.

The lunch Saturday at Seoul's presidential mansion between Moon and Kim Yo-jong was the most significant diplomatic encounter between the rivals in years. The night before, Kim Yo-jong and other North Korean delegates attended the opening ceremony of the Pyeongchang Winter Olympics, watching a "unified" Korean team march under a banner showing an undivided Korean Peninsula.

In a surreal mixture of dignitaries, the Olympic Stadium's VIP box included Kim Yo-jong and North Korea's nominal head of state, Kim Yong-nam, sitting above and behind U.S. Vice President Mike Pence and fellow hardliner Shinzo Abe, the leader of Japan. Pence and the Kims seemed to go out of their way not to acknowledge each other.

Kim Yo-jong, sister of North Korean leader Kim Jong-un, arrives at the opening ceremony of the PyeongChang 2018 Winter Olympic Games on Friday. She has delivered her brother's invitation to South Korea's President to visit the North at a 'convenient time.' (Patrick Semansky/Getty Images)

That was not the case with Moon — either at the games, when he enthusiastically reached up to shake Kim Yo-jong's hand, or at the lunch the next day. South Korean television showed its smiling president entering a reception room Saturday and shaking hands with the North Koreans.

The public part of the talks was mostly about the weather: Pyeongchang was colder than Seoul, it was agreed.

"You went through a lot of trouble braving the cold until late" last night, Moon told the North Koreans, referring to their attendance at the frigid opening ceremonies.

Kim Jong-un's hand-delivered letter

After sitting at a table, Kim Yo-jong placed a blue document folder in front of her. She later gave that folder to Moon, and Moon's office said it was a personal letter from her brother. Officials didn't reveal what was written in it.

After meeting with Moon, the North Korean delegates boarded a bullet train to Gangneung, a coastal city hosting some Olympic events. Later Saturday night, they all joined the chief of the International Olympic Committee to watch the debut of the inter-Korean team at the women's ice hockey tournament against Switzerland, which pulled to an early 3-0 lead.

Pence's office didn't directly address Kim's invitation to Moon. "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," Pence spokeswoman Alyssa Farah said when asked about the developments.

Moon is eager to use Kim's presence at the games to restore regular communication with North Korea and eventually pull it into nuclear talks. Many in Seoul, however, while interested in the warming high-level contacts, are also tempering expectations for a real breakthrough.

There's worry, too, that the proposed summit Pyongyang may come with preconditions — a North Korean specialty. A big one could be a demand to cease the U.S.-South Korean war games that North Korea claims are preparation for invasion.

But Moon, a liberal who has always wanted to engage the North, will also have to convince a good portion of his own people who are deeply wary about North Korean intentions.

Throw in there the accusations that South Korea has had to arrange huge payouts for past meetings, and that these earlier encounters, while producing indelible images, have done little to slow North Korea's pursuit of nuclear weapons.

Even if there are more meetings between the rivals after the Games, accomplishing something is another matter. South Korea wants a northern neighbor without nukes; North Korea vows to keep its weapons until the United States discards its "hostile" policies against the country.

Japan warning about 'smile diplomacy'

Hours before Friday's opening ceremony in Pyeongchang, Japan's Abe warned Moon not to fall for North Korea's "smile diplomacy" during the Olympics, according to Moon's office. Pence carried a similar message.

They seem to have gone unheeded.

"Kim Jong-un is clearly serious about reviving talks with the South to improve relations," said Koh Yu-hwan, a North Korean expert at Seoul's Dongguk University and a security adviser to Moon.

"It seems clear," he said, "that the countries have entered a phase of restoring a regular level of contact."