|North Korean state media has urged people to pledge allegiance to Kim's youngest son Kim Jong-un [AFP]
The young man tipped to be North Korea's next leader and propel the Kim dynasty into a third generation is even more of an enigma than his mercurial father Kim Jong-il, who has died at the age of 69.
North Korean state media on Monday urged people to pledge allegiance to Kim's youngest son and heir apparent Kim Jong-un, aged in his late 20s, after the stunning announcement that his father had died on Saturday.
Kim Jong-un's life is shrouded in mystery, but in recent years he has been pushed to the forefront as his father apparently sped up plans for the nation's second dynastic succession, after suffering a stroke in August 2008.
In September 2010, the son was made a four-star general and given senior ruling party posts, despite his lack of any military experience.
It was only then that state media published his first-ever adult photograph, an image of a chubby young man dressed in a dark Mao-type suit sitting in a line-up of top communist party officials.
Since his elevation, Kim Jong-un has been constantly at his father's side, and is said to be actively involved in state affairs.
Kim Jon-il's youngest son, Kim Jong-un is expected to take over from his father [Al Jazeera]
North Korea's propaganda machine has rolled into action to build up the same personality cult for Jong-un that surrounded his father and late grandfather Kim il-Sung, the founder and "eternal leader" of North Korea who died in 1994.
The North's official media on Monday declared Jong-un as the "great successor", in a sign that North Korea's elites have signed up to a well-planned handover of power.
"Kim Jong-un's leadership provides a sure guarantee for creditably carrying to completion the revolutionary cause of juche through generations, the cause started by Kim il-Sung and led by Kim Jong-il to victory," the official news agency said.
However, little is known about how the succession will unfold in the world's only communist dynasty.
Kim Jong-il's only sister Kim Kyong-hui and her husband Jang Song-thaek, the country's unofficial number-two leader, are expected to act as Kim junior's mentor and throw their political weight behind him.
Although many observers have played down any immediate turbulence in the nuclear-armed nation, they say that the longer-term scenario for the secretive nation remains unclear.
"The North Korean elite has a vested interest in maintaining the system and will assess Jong-un's ability to protect its interests," said Bruce Klingner, a Northeast Asia expert at the Heritage Foundation in Washington.
The son is not only inexperienced but lacks his own power base, Klingner said, pointing to reports that top officials seen as resistant to a third-generation dynastic succession had been removed.
"The elite will balance a shared sense of external threat against fear of domestic instability from an inexperienced leader. The senior government leadership may assess Jong-un's shortcomings as sufficient justification for contesting his succession," he said.
In a memoir, Kenji Fujimoto, a former Japanese sushi chef for Kim Jong-il, described the Swiss-educated Jong-un as a "chip off the old block, a spitting image of his father in terms of face, body shape and personality".
Jong-un has made headlines since his name was floated by South Korean media in early 2009 as the figure being groomed to succeed his father.
Little is known for sure about his character but experts believe he has traits in common with his father.
"Jong-un is known to have the potential to become a strong, ruthless leader. He has a take-charge personality," Sejong Institute analyst Cheong Seong-chang, a specialist in the succession issue, has told AFP previously.
"As a result, as of the summer of 2010, Kim Jong-un peddles influence, excluding in foreign affairs matters, on state affairs on a level similar to that of Kim Jong-il."
South Korea's spy chief Won Sei-hoon said last year that Kim Jong-il's poor health had driven him to speed up preparations for the transfer of power, with the son taking a bigger policy-making role and accompanying his father on trips.
Some analysts had seen second son Kim Jong-chul as favourite to take over. But Fujimoto said in his memoir that Kim thought of Jong-chul as effeminate and unfit for leadership.
Eldest son Jong-nam apparently spoilt his prospects after being deported from Japan in 2001 for trying to enter with a forged passport while attempting a visit to Tokyo Disneyland.
Jong-un was born to the leader's third wife, Japan-born ethnic Korean dancer Ko Yong-hi, who is believed to have died of breast cancer in 2004. He is believed to have studied at international school in Switzerland under a false name.
Newspaper reports say he enjoyed basketball and drawing cartoons in Switzerland, where school staff and friends reportedly remembered a shy boy who liked skiing and Hollywood tough guy Jean-Claude Van Damme.