Kim Yo Jong's promotion solidifies her position in Pyongyang's circles of power

Ms Kim Yo Jong standing beside her brother, North Korean leader Kim Jong Un, during the Inter-Korean summit at the Peace House in Panmunjom on April 27, 2018. PHOTO: AFP/KOREA SUMMIT PRESS POOL

SEOUL (AFP) - Sister, adviser, and now top official: the latest promotion of Ms Kim Yo Jong, sibling to North Korea's leader, solidifies her position in Pyongyang's circles of power, analysts say.

She has long been among Mr Kim Jong Un's closest lieutenants and one of the most influential women in the isolated regime, and on Thursday (Sept 30) it was made official when state media announced she had been named to the State Affairs Commission (SAC), the country's top government body.

It is a major step up from her relatively junior position as a vice-department director in the ruling party, and is likely to heighten speculation that she could be a long-shot candidate to succeed her brother - whose health is a regular topic of rumour - in the event of his demise.

Such a transition would give the socially conservative North its first female leader, but analysts caution it would defy convention.

"Kim Jong Un has raised Kim Yo Jong's status," said Dr Shin Beom-chul, a researcher at the Korea Research Institute for National Strategy.

Born in 1988, according to Seoul's Ministry of Unification, Ms Kim is one of three children born to Mr Kim's predecessor Kim Jong Il and his third known partner, former dancer Ko Yong Hui.

She was educated in Switzerland alongside her brother and rose rapidly up the ranks once he inherited power after their father's death in 2011.

Her existence was barely known to the wider world until her father's funeral, when she was seen on state television standing right behind Mr Kim Jong Un, looking tearful and ashen-faced.

In contrast, an inscrutable smile played on her lips when she rode down an escalator at Incheon airport as her brother's envoy to the 2018 Winter Olympics, becoming the first member of the North's ruling dynasty to set foot in the South since the Korean War.

Every detail of her visit was closely watched, from the clothes she wore to the bag she was carrying and even her handwriting.

In keeping with the secrecy shrouding North Korea's leaders, it is not known whether she is married.

More recently, she has often been seen at her brother's side, including at his summits with the South's leader Moon Jae-in and then United States President Donald Trump: on their 60-hour train journey to Hanoi for a meeting which then collapsed, she was seen bringing Mr Kim an ashtray when he stepped off for a cigarette break.

She has also regularly issued statements in her own name, making vitriolic denunciations of Washington or Seoul, particularly ahead of the North blowing up a liaison office on its side of the border last year that the South had built and paid for.

There was "no doubt" that Mr Kim has an exceptionally close relationship with his sister, said Dr Yang Moo-jin of the University of North Korean Studies in Seoul.

"Jong Un and Yo Jong spent much of their lonely childhood overseas together - I think this is when they developed something that is similar to comradeship, on top of sibling love," he said.

'Paektu bloodline'

Leadership has always been a family affair in the North and other than her brother, Ms Kim is now the highest-ranked member of the "Paektu bloodline" - a Northern term for the siblings' grandfather Kim Il Sung and his descendants, who have led the nuclear-armed country since its foundation.

When Mr Kim disappeared from public view for several weeks last year, it triggered feverish speculation over his health and who might succeed him.

Analysts say Ms Kim's portrayals in state media could be intended to bolster her credibility with the North Korean military and other hawks.

But when the official Rodong Sinmun newspaper carried portraits of the eight new SAC appointees on Thursday, she stood out among them both as the only woman and for her youth.

Given North Korea's social and political structures, said Dr Park Won-gon, a professor of North Korean studies at Ewha Womans University, it would be "very difficult" for Mr Kim to designate his sister as his successor, "even though she is a member of the Paektu bloodline".

Join ST's Telegram channel and get the latest breaking news delivered to you.