SEOUL, South Korea -- North Korean leader Kim Jong Un's influential sister has been appointed to the country's top government body, the official KCNA news agency reported Thursday.

Kim Yo Jong, a key adviser to her brother, was promoted to a position on the State Affairs Commission, amid a raft of changes approved by the Supreme People's Assembly, the rubber-stamp parliament.

No fewer than nine members of the commission were dismissed, including one of its vice-presidents, Pak Pong Ju, and diplomat Choe Son Hui, a rare senior woman in the North's hierarchy who has played a key role in negotiations with the United States.

The official Rodong Sinmun newspaper carried portraits of the eight new appointees on Thursday, Kim Yo Jong standing out among them both for her youth and as the only woman.

She has often been seen in close proximity to her brother -- with whom she went to school in Switzerland -- including at his summits with then-US president Donald Trump and the South's leader Moon Jae-in.

Her exact political role has long been the subject of speculation -- as has the possibility that she might one day succeed her brother, a transition that would give the socially conservative North its first female leader.

She has at times made vitriolic denunciations of Washington or Seoul in statements carried by state media, particularly ahead of the North blowing up a liaison office on its side of the border that the South had built and paid for.

Her relatively junior position as a vice department director of the Central Committee of the ruling Workers' Party gave those declarations an element of ambiguity, and in some cases, she specifically said she was speaking in a personal capacity.

Her official rank has risen and fallen over time, but her new SAC position is by far the most senior post she has held.