INCHEON, SOUTH KOREA (AFP, REUTERS) - An aircraft carrying the sister of North Korean leader Kim Jong Un and the country's ceremonial head of state Kim Yong Nam landed in the South on Friday (Feb 9), television pictures showed, in a historic first.

The white Ilyushin-62 aircraft, marked in Korean script "Democratic People's Republic of Korea", the North's official name, and its tailfin emblazoned with a Northern emblem, touched down at Incheon airport near Seoul.

On board were Kim Yo Jong, the first member of the North's ruling dynasty to visit the South since the Korean War ended with a ceasefire in 1953, and Kim Yong Nam, the leader of its delegation to the Winter Olympics in the South.

Police formed barricades inside Incheon airport, from where the delegation was to leave for mountain resort of Pyeongchang.

The pair were greeted at the airport by South Korean Unification Minister Cho Myong Gyon. They will have lunch with South Korean President Moon Jae In on Saturday (Feb 10), the presidential office said.

Their visit is the diplomatic high point of an Olympics-driven rapprochement between the two sides of the divided peninsula, which remain technically at war.

Kim Yo Jong, believed to be aged 30, is one of three children born to former North Korean leader Kim Jong Il and his third known partner, former dancer Ko Yong Hui, making her a full sister of Kim Jong Un.

Meanwhile, Kim Yong Nam and US Vice-President Mike Pence are set for their first face-to-face encounter on Friday when they attend the opening ceremony of the Olympics.

Pence arrived in South Korea on Thursday and had talks and dinner with Moon, both reiterating their commitment and cooperation to defuse tensions on the Korean peninsula sparked by North Korea's missile and nuclear programmes.

He met North Korean defectors on Friday and was expected to pay tribute at a memorial for 46 South Korean sailors killed in 2010 in the sinking of a warship that Seoul blamed on a North Korean torpedo attack.

'MAXIMUM PRESSURE'

The move by Pence, who has described the North as the "most tyrannical and oppressive regime", is in line with Washington's campaign to put "maximum pressure" on Pyongyang.

Pence has kept open the possibility for some contact with the North Koreans in South Korea, while reiterating Washington's insistence that denuclearisation is a necessary condition for peace on the Korean peninsula.

Pence, Kim Yo Jong and other world leaders will attend the opening ceremony in Pyeongchang, just 80 km from the heavily fortified border between North and South Korea, later on Friday.

Moon will also hold a welcoming reception for his top guests before the opening, a presidential official said, where Pence and Kim Yong Nam could sit at the same table with Moon.

The Games will see athletes from the two Koreas march together under one peninsula flag for the first time in more than a decade.

Nearly 500 North Koreans are participating in the Olympics, which run through to Feb 25, including a cheering squad, art troupe and taekwondo demonstration team, the South's Unification Ministry said.

However, the inter-Korean Olympics detente has raised concerns in Washington and Tokyo that Seoul may undermine the US-led campaign of global pressure to get Pyongyang to abandon its nuclear and missile programmes.

Moon is also scheduled to hold a summit with Japanese Prime Minister Shinzo Abe, during which they are expected to discuss the North Korea standoff and the sensitive issue of "comfort women", a euphemism for girls and women forced to work in Japan's wartime brothels.

Abe said before leaving for the Olympics he wanted to convey to the world that cooperation among the United States, Japan and South Korea on the North Korean threat "will not waver".