North Korean leader Kim Jong Un's sister Kim Yo Jong arrived in the South with Kim Yong Nam, the North's nominal head of state, for the opening ceremony of the Winter Olympics.

Ri Son-kwon, chairman of the Committee for the Peaceful Reunification of the Fatherland whispers to Kim Yo-jong, the sister of North Korea's leader Kim Jong-un before their meeting at the Presidential Blue House in Seoul, South Korea, February 10, 2018.
Ri Son-kwon, chairman of the Committee for the Peaceful Reunification of the Fatherland whispers to Kim Yo-jong, the sister of North Korea's leader Kim Jong-un before their meeting at the Presidential Blue House in Seoul, South Korea, February 10, 2018. (Reuters)

South Korean President Moon Jae In's office says his lunch meeting with senior North Korean officials including leader Kim Jong-un's sister has ended.

Kim Yo Jong and other North Korean delegates, including the country's 90-year-old nominal head of state Kim Yong Nam, arrived in the South on Friday on Kim Jong Un's private jet and attended the opening ceremony of the Pyeongchang Winter Olympics.

The meeting tool place at the presidential palace in the most significant diplomatic encounter between the rivals in years.

At the Olympic Stadium's VIP box, Kim Yo Jong and North Korea's nominal head of state, Kim Yong Nam, took their place among dignitaries from around the world, including US Vice President Mike Pence who sat just a few feet (less than a metre) away and seemed to make an effort not to acknowledge them.

South Korean television showed a smiling Moon entering a reception room and shaking hands with the North Koreans, who also included Choe Hwi, chairman of the country's National Sports Guidance Committee, and Ri Son Gwon, chairman of the North's agency that deals with inter-Korean affairs.

"You went through a lot of trouble braving the cold until late," he told them.

Journalist Eunice Kim reports from Seoul.

It's still unclear whether Saturday's event could be used to set up bigger meetings between the Koreas. Lawmakers from Moon's liberal ruling party have talked about the possibility of South Korea sending a special envoy to Pyongyang to meet with Kim Jong Un. There's even speculation of a summit between Kim and Moon.

Kim Yo Jong, 30, is the first member of North Korea's ruling family to visit the South since the end of the 1950-53 Korean War.

Saturday's meeting was the first time a South Korean president hosted North Korean officials for a luncheon at the Blue House since November 2007, when late liberal President Roh Moo Hyun, the political mentor of Moon, invited then-North Korean premier Kim Yong Il following a meeting with government officials in Seoul.

However, no member of North Korea's ruling family has ever before visited the Blue House.