The powerful sister of North Korean leaderKim Jong Unhas been given a promotion in the ruling party structure during a rare party congress, state media reported Tuesday.

The Workers Party Central Committee on Monday namedKim Yo Jongpreviously a deputy department director as a full department director, Pyongyangs official Korean Central News Agency (KCNA) said.

Thousands of party elites have packed the capital, Pyongyang, for a once-in-five-years summit of the ruling Workers Party, a gathering that directs state efforts on everything from diplomacy to war planning.

The congress offers a rare glimpse into the political workings of reclusiveNorth Koreaand is widely seen as a forum for Kim to flex his grip on power.

Kim Yo Jong has long been among her brothers closest lieutenants and one of the most influential women in the isolated regime.

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Born in the late 1980s, according to the South Korean government, she is one of three children born to Kims father and predecessor,Kim Jong Il, and his third known partner, former dancer Ko Yong Hui.

She was educated inSwitzerlandalongside her brother and rose rapidly up the ranks once he inherited power after their fathers death in 2011.

In 2018, she visited South Korea for the Pyeongchang Winter Olympics, during a period of inter-Korean rapprochement.

Pyongyangalso frequently uses her name to issue statements outlining its positions or criticising the South and the US.

Heir apparent

Later in the days-long congress, Kim Jong Un is expected to unveil the next phase inNorth Koreas nuclearweapons programme.

The countrys nuclear arsenal has been transformed under Kim from a source of mild global concern to something treated as a genuine threat.

It is just the ninth time the Workers Party congress has convened under North Koreas decades-spanning Kim rule.

Read moreKim Jong Un opens North Koreas 9th party congress, highlights economic gains

Particular attention will also be placed on the whereabouts ofKims teenage daughter, Ju Ae, who has emerged as North Koreas heir apparent, according to Seouls National Intelligence Service.

At the previous congress five years ago, Kim declared that theUnited Stateswas his nations biggest enemy.

There is keen interest in whether Kim might use the congress to soften this stance or double down.

US PresidentDonald Trumpstepped up his courtship of Kim during a tour of Asia last year, saying he was100 percent opento a meeting.

Kim has so far largely shunned efforts to resume top-level diplomatic dialogue.

(FRANCE 24 with AFP)

Originally published on France24