North Korea's state news agency KCNA has called dead leader Kim Jong Il's son Jong Un a "great successor" in what appears to be the first such mention of the late leader's youngest known son, who had been groomed to take over power.
Jong Un is the "great successor to the revolutionary cause of Juche and outstanding leader of our party, army and people," KCNA said. Juche is the North's homegrown political ideology of self reliance.
Not much is known about the younger Kim, not even his age, though his father, Kim Jong Il, and his autocratic regime had begun making preparations for the son's transition to power.
Thought to be aged around 27, Kim Jong Un had already been made a four-star general and occupied a prominent political post when he was reported to have made an important diplomatic visit to neighboring China in May this year.
On the trip, he introduced himself to the destitute North's main benefactor, possibly one of the most crucial diplomatic moves he will ever make.
'Basically a kid'
"The rest of the world is going to have to look at someone who is basically a kid as having China's support to be the North's next leader," Yang Moo-min, of Seoul's University of North Korean Studies, said at the time.
The youngest of the leader's three sons, Kim was most likely born in 1984. His name in Chinese characters translates as "righteous cloud" while the media calls him "the young general."
Experts say the young Kim is likely to follow the same militaristic path as his father, maintaining a strong grip over one of the world's largest armies and pressing on with a nuclear weapons program in the face of international outrage.
Two attacks on the peninsula last year, which killed 50 South Koreans, were aimed at winning the army's support for a continuation of dynastic rule and underscored an intent to retain the state's military-first policy, according to analysts.
Diplomatic breakthrough at risk?
However this week could have seen a significant diplomatic breakthrough in talks over the North's nuclear program.
The Obama administration had been poised to announce a significant donation of food aid to North Korea this week — possibly as early as Monday — in the first concrete accomplishment after months of behind-the-scenes diplomatic contacts, according to sources close to the negotiations.
An agreement by North Korea to suspend its controversial uranium enrichment program had been expected to follow within days, the sources said.
The officials, who spoke on condition of anonymity due to the sensitivity of the situation, said Kim's death would likely delay the effort.
NBC News reported that Kim Jong Il's death was a big shock to U.S. intelligence. While the U.S. was well aware of his medical condition and has been working on transition scenarios for years, the announcement of his death came out of the blue.
Educated in Switzerland, Kim Jong Un is thought to speak English and German, and bears a striking resemblance to his grandfather, the North's founder, Kim Il Sung.
Last year, the young dauphin was officially anointed as leader-in-waiting when his father made him a four-star general and gave him a prominent political post. But for added security, Kim promoted his sister and her husband to top positions to create a powerful triumvirate to run the family dynasty.
Despite speculation that Kim Jong Il's rule was nearing its end, after he reportedly suffered a stroke in 2008, the "Dear Leader" increased his workload and appeared to be physically stronger in recent months.
There have also been few signs of regime change, with no overt signs of crisis or instability.
"Despite economic hardship, food shortages, and a welter of sanctions, the Kim Jong Il regime seems stable, and the succession process is, by all appearances, taking place smoothly," John Delury and Chung-in Moon of Yonsei University wrote in an article in April.
Moreover, the two scholars say China is actively engaged on diplomatic and economic levels in supporting North Korea's survival, stability and development.
China prefers the status quo on the peninsula, worried that if the South takes over the North, the South would bring its U.S. military ally to the Chinese border.
Cloak of secrecy
The most frequently viewed photograph of Jong Un before his emergence last year was of him as an 11-year-old. But recent pictures and footage of him show a heavy-set young man with his hair clipped short to resemble the young leader Kim Il Sung.
There is a question over whether his late mother, a Japanese-born professional dancer called Ko Yong-hui, was Kim Jong Il's official wife or mistress — an issue that might weigh on his legitimate right to replace his father.
Even by intensely secretive North Korean standards, remarkably little is known about the son, whose youth is also a potential problem in a society that values seniority.
Dr John Swenson-Wright, associate fellow of the Asia program at London-based think tank Chatham House, told msnbc.com that the change of leadership in North Korea presented "both opportunities and potential hazards" for its neighbors and Western countries.
"Kim Jong Un is very untested and little is known about his temperament and he has not held high office," he said.
Kim Jong Un reportedly is a fan of James Bond and basketball star Michael Jordan.
Joao Micaelo told CNN that he believes Kim Jong Un was one of his classmates in Switzerland between 1998 and 2001.
"He was a normal guy like me," Micaelo said. "He was competitive at sports. He didn't like to lose, like any of us. For him, basketball was everything."
Although the student used the name Pak Un, Micaelo said his friend once claimed that he was "the son of the leader of North Korea."
Kim Jong Il was very publicly named heir by his father, Kim Il Sung, but he studiously avoided repeating the process and for years none of his three sons appeared in state media.
Kim Il Sung, the "eternal president," died in 1994.
After taking over from his father, Kim Jong Il saw his state's economy grow weaker and a famine in the 1990s killed about one million of his people, while he advocated a military-first policy.
In a book about his time as chef to the ruling household, Kenji Fujimoto of Japan said that of the three sons, the youngest, Kim Jong Un, most resembled his father.
He is also said to have a ruthless streak and the strongest leadership skills of the three. He was also thought to be his father's favorite.