The youngest son of North Korean leader Kim Jong Il was elected to his first prominent posts in the ruling Workers' Party, state media said early Wednesday, putting him well on the path to succeed his father as leader of the nuclear-armed nation.

The announcement of Kim Jong Un's ascension to the party's Central Committee and military commission came a day after news that Kim Jong Il had made him a four-star general — a major promotion that appeared to set into motion a plan to eventually put the little-known, Swiss-schooled 20-something at the helm of the communist country.

Kim Jong Il has led the nation with absolute authority since taking over in 1994 upon the death of his father, North Korea founder Kim Il Sung, in the communist world's first father-to-son transfer of power.

Speculation has been brewing about another dynastic succession since the 68-year-old reportedly suffered a stroke in August 2008. There are concerns that his sudden death without a leadership plan in place could spark chaos in the nation of 24 million that he rules under a "military-first" policy.

Noticeably thinner and grayer, Kim Jong Il has resumed touring factories and farms but is said to be suffering from diabetes and kidney trouble.

However, none of his sons appears ready to step into the limelight. The eldest, Jong Nam, spends much of his time outside the country and may have thwarted his chances by getting caught trying to sneak into Japan on a fake passport in the 1990s. The father thinks the middle son, Jong Chol, is too girlish, according to a 2003 memoir by a former sushi chef who worked for the leader.

Kim Jong Un is believed to be only 27 and until this week held no known political or military positions. However, he was always his father's favorite, and the most like him in looks and ambition, the chef wrote in "I Was Kim Jong Il's Cook" under the pen name Kenji Fujimoto.

The son has been kept well under wraps since childhood, and the mere mention of Kim Jong Un's name in state media caused ripples among North Korea watchers looking for confirmation that Kim Jong Il had anointed the young man as his successor.

"It's clearly the biggest news we've had from North Korea since the death of Kim Il Sung," said Peter Beck, a Council on Foreign Relations-Hitachi research fellow at Keio University in Tokyo.

The secrecy is reminiscent of Kim Jong Il's own ascent in the 1970s, when his status as the nation's future leader was confirmed in an appearance at the last major Workers' Party gathering: a party congress in 1980.

However, L. Gordon Flake, executive director at the Mansfield Foundation, said speculation about power hand-offs in the North is premature.

"There is no succession as long as Kim Jong Il is alive," Flake said. "What we are witnessing here is the early indication of the beginning steps of the process of succession. ... Kim Jong Il is still in power."

But, he said, it is clear that Kim Jong Un is being thrust into positions of power earlier than Kim Jong Il was. "Clearly, the process is being rushed," he said, adding: "It's a pretty big jump up to a four-star general in a day."

Kim Jong Un was named a vice chairman of the party's Central Military Commission, which formulates the party's military policies, directs the country's 1.2 million-member army and oversees military projects, according to South Korea's Unification Ministry.

He also won a spot on the party's Central Committee, the official Korean Central News Agency said in a dispatch from Pyongyang. The Central Committee oversees the powerful Political Bureau and Secretariat, and functions as the party's top decision-making body when national congresses are not convened.

Kim Jong Il was named to the committee in 1972, two years before he was tapped as the country's next ruler, the Unification Ministry said.

Kim also appeared to be tightening the circle of power around the Kim family by elevating his sister and her husband.

Sister Kim Kyong Hui, 64, retained her position as a department director on the Central Committee and gained a new post as a member of the Central Committee's Political Bureau.

"There is a possibility that she could play the role of a coordinator to make sure the power succession goes smoothly," said analyst Cheong Seong-chang, of the Sejong Institute think tank.

Her husband, Jang Song Thaek, built on his nomination in June to the No. 2 position on the National Defense Commission with three posts: alternate member of the Political Bureau, department director for the Central Committee and a spot on the military commission, according to KCNA.

Their promotions indicate Kim is keeping it all in the family until the son is ready to take over, analysts said.

Pyongyang was in a festive mood Tuesday, with banners and placards hailing the Workers' Party celebration lining the streets, according to broadcaster APTN.

"This meeting of the delegates is an important occasion for further strengthening the solidarity of our army, our party, and our people, who are rallying behind the great Gen. Kim Jong Il," Kim Chang Gyong, an assistant professor at North Korea's Academy of Social Sciences, told the broadcaster.

Earlier, the U.S. State Department called the political meeting "the ultimate reality show."

Spokesman P.J. Crowley told reporters in Washington on Tuesday that U.S. officials were watching the gathering and what happens with Kim Jong Un closely, adding that the outcome would have "implications on our present and future policies." He didn't elaborate.