Kim Jong-un's sister arrives in South Korea, making history

North Korean leader Kim Jong-un's younger sister arrived in South Korea on Friday to begin an unprecedented three-day visit that started with her attendance at the opening ceremony of the Pyeongchang Winter Olympics.

She also plans to sit down with South Korean President Moon Jae-in for a luncheon at the presidential Blue House in Seoul.

Kim Yo-jong, who is probably her brother's closest confidant and is a senior cadre in North Korea's ruling party, is the first member of the family dynasty to visit South Korea. However, her grandfather, Kim Il-sung, travelled to areas occupied by his troops south of what is now the Demilitarized Zone during the 1950-53 Korean War.

The trip has the potential to become something of a coming out party — certainly for Kim Yo-jong, but also for her deeply isolated country.

Kim Jong-un hasn't set foot outside North Korea or met a head of state since assuming power upon the death of their father, Kim Jong-il, in late 2011. His pursuit of a nuclear arsenal to counter what he sees as the threat of invasion by the United States has ratcheted up tensions not only with his rivals, but also with primary trading partner China and Russia, once a key benefactor.

Kim Yo-jong's arrival was broadcast live on South Korean television. Looking confident and relaxed, she had a brief meeting with South Korean officials, including Unification Minister Cho Myoung-gyon, before being whisked away in a black limousine and catching the high-speed train to Pyeongchang.

Rising political figure

At 30, she is probably the most powerful woman in North Korea.

She has been rapidly rising within the North's power structure and is believed to be in charge of shaping her brother's public persona. But she has generally remained safely cloaked in her brother's shadow. This is her first high-profile international appearance at centre stage, though she is technically just a member of a delegation headed by the North's senior statesman, 90-year-old Kim Yong-nam.

Just before the opening ceremony, Kim Yong-nam, the highest-ranking North Korean official to travel to the South, attended a dinner for visiting foreign dignitaries hosted by Moon. U.S. Vice-President Mike Pence was at the dinner and also attended the opening ceremony. Pence did not meet with the North Korean delegates, spokesperson Alyssa Farah said.

However, UN Secretary General Antonio Guterres did meet briefly with Kim Yong-nam while attending the opening ceremony, a UN spokesperson said Friday.

"He did have a brief exchange with President Kim in which he once more reiterated... that his expectation and hope is that all parties will use dialogue to achieve a peaceful denuclearization of the Korean peninsula," Farhan Haq told reporters.

For security reasons, few details of Kim Yong-nam's three-day itinerary have been made public.

After arriving on Kim Jong-un's personal jet at the South's ultra-modern Incheon International Airport — the North's flagship airline is subject to sanctions — she travelled to Pyeongchang to attend the Games' opening ceremony, where the North and South Korean athletes marched together behind a blue-and-white "unification" flag.

The two Koreas, which remain technically at war, have cycled through countless periods of chill and thaw since their division 70 years ago. North Korea boycotted the 1988 Summer Olympics in Seoul and blew up a South Korean commercial airliner the year before. The past year has been particularly acrimonious as the North has accelerated its nuclear weapons development and test launches of missiles that are now believed to be able to reach most or all of the United States, South Korea's most important ally.

Blue House meeting

The delegation's most substantive event may come outside the Olympic ambit on Saturday.

Along with the rest of the North's senior delegation, Kim Yo-jong is to have lunch with Moon in Seoul. The meeting could turn out to be just a lunch, a photo-op or a nicety. But it is so unprecedented, and its announcement on Thursday was so sudden that rumours are already swirling it could open the door to much more — perhaps even an offer for Moon to travel to Pyongyang, North Korea's capital.

The North and South held summits in Pyongyang in 2000 and 2007, both hosted by Kim Jong-il.

Caution is in order here: Considering the depth and complexity of the very real problems that keep the Koreas apart, it's highly unlikely a luncheon would lead to an immediate breakthrough on something like the North's nuclear weapons development.

Pence, who is using his visit to South Korea to underscore the Trump administration's policy of maximum pressure on the North, has publicly and repeatedly warned Seoul not to let down its guard to a North Korean charm offensive.

Even so, just holding such a meeting seemed unimaginable only a few months ago.