SEOUL, South Korea – Secretive North Korea said Saturday it will choose new ruling party leaders later this year — a surprise announcement that is intensifying speculation the regime is setting the stage for 68-year-old supreme ruler Kim Jong Il’s youngest son to eventually succeed him.

The question of who will take over from Kim is important because the leader — as presumably his successor would be — holds absolute power in the impoverished country, which has active nuclear and missile programs and regularly threatens to destroy rival South Korea.

Many fear political instability or even a power struggle if Kim, who rules North Korea through his position as chairman of the powerful National Defense Commission, were to die or become incapacitated without clearly naming a successor.

Kim himself was publicly groomed for years to succeed his father — North Korea’s founder, Kim Il Sung, who ruled the country for nearly five decades. He died in 1994.

The North may not have the luxury of such a long transition this time. Kim is believed to have had a stroke in 2008, and there have been reports his memory is slipping. In addition, after years of relatively good relations with Seoul, ties have become strained again, exacerbated most recently by the sinking of a South Korean navy ship blamed on Pyongyang. The North has denied the allegation.

The North is also facing economic woes that have worsened after a botched currency reform last year, and finds itself increasingly isolated in a standoff with the international community over its nuclear program.

Kim Jong Il has yet to send a clear signal to the outside world whom among his three sons he favors. Many analysts believe, however, that he has already tapped Kim Jong Un, the youngest, to assume the reins.

So Saturday’s announcement that the Workers’ Party of Korea would convene its first conference since 1966 to elect a new ruling body has increased speculation leaders may be laying the groundwork for such a succession.

The official Korean Central News Agency did not say what posts would be up for grabs, but the party’s top bodies include a central committee, a politburo and a secretariat. The party’s inner workings are murky. Earlier this month, a candidate proposed by the politburo was named the country’s new premier.

KCNA emphasized in its report Saturday that 2010 will be a year of “great changes to be specially recorded in the history of the country.” It also described Kim Jong Il as being held in “high esteem at the highest posts of the WPK and revolution,” indicating his position as head of the party was unlikely to change.

Some suggested, however, that officials loyal to Kim Jong Un could be elected to senior party positions at the September conference and that the young man himself could even be given senior party responsibilities.