Kim Jong-un expected to 'promote his sister' at North Korea's first party congress for 36 years

North Korea's Workers' Party will open its first congress in 36 years on Friday, with Kim Jong-un, the youthful dictator, expected to use the occasion to promote his younger sister and tighten his grip on power.

Kim Yo-jong, the 29-year-old sister of the “Supreme Leader”, is presently a deputy director of the party's central committee, responsible for overseeing propaganda.

Experts believe the congress will confirm her promotion, possibly to the leadership of the central committee. "There is a high possibility that Kim Yo-jong will be promoted to the director as she has built field experience by helping Kim Jong-un over the past three years," said Yang Moo-jin, a professor at the University of North Korean Studies in Seoul, according to Yonhap News.

Ms Kim studied in Switzerland at the same time as her brother and media reports have suggested that she is already in charge of Mr Kim’s daily schedule, as well as “his fashion and hairstyle".

Ms Kim is believed to have become the number two person in the family-run regime. Her promotion at this congress would help her brother to cement his rule.

In the run-up the event, North Korea’s propaganda machine has described Mr Kim as the “great sun of the 21st century" and hailed his achievements, including the acquisition of the "precious sword" of nuclear weapons.

Weddings and funerals have been banned for the duration of the congress, which is expected to last three days, and travel restrictions imposed across the country. Security has also been tightened along North Korea’s borders. The latter precautions are designed to deter any embarrassing defections during the congress.

Why Mr Kim has chosen to call the first party congress since 1980 is unclear. Some experts believe his sole purpose is to use the occasion to tighten his grip as dictator for life.

"His only aim is to consolidate his role as the new supreme leader", said Rah Jong-yil, a former head of South Korean intelligence. "I do not expect him to announce any significant reforms, as other communist leaders eventually conceded they had to do, and the congress will revolve around Mr Kim.”

But some experts believe that he could announce reforms to North Korea’s struggling economy, following China’s example.

Toshimitsu Shigemura, a professor at Waseda University in Tokyo and an authority on North Korea’s leadership, said there could be a shift away from the long-held "military-first" policy. "Mr Kim is determined to increase the power of the party at the expense of the military and I expect him to try to weaken the influence of the National Defence Committee", he said. "That would enable him to declare a 'new era' that is more focused on the people".

Mr Kim has already sacked or, in some cases, executed numerous members of the "old guard" in the North Korean military, meaning that there is less opposition to his diktats.

Prof Shigemura warned, however, that the army was unlikely to accept being downgraded, creating the possibility of unrest.

Another possibility is that Mr Kim may order a fifth nuclear test or another series of missile drills to coincide with the congress, although recent satellite images show only limited activity at the nuclear testing facility at Punggye-ri

Mr Rah said he does not expect another show of force during the congress and a "period of relative calm" was likely. Professor Shigemura concurred, adding that Mr Kim could declare that North Korea already is a nuclear power which no longer needs to carry out tests. This, in turn, would enable the regime to seek to rebuild bridges with China and possibly the US.