North Korea leader Kim Jong-il and his heir apparent son watched a art performance celebrating the birthday of his late father and founder of the communist country, a state-run media organ reported Saturday.

"Kim Jong-il enjoyed a performance given by the art squad of the National Security Agency on the occasion of the Day of the Sun," the North's state-run Korean Central News Agency monitored in Seoul said. As is customary, the KCNA didn't report on when Kim watched the performance and where.

The "Day of the Sun," which is the official name given by the North to mark Kim Il-sung's birthday that falls April 15, is one of the most important holidays in the isolated country.

The report said performers sang various songs such as the "Song of Happiness" and "Our Unforgettable Leader" and lauded the 99th anniversary of the founder's birthday as a great, auspicious event in human history.

The KCNA added that Kim Jong-il expressed great satisfaction with the performance that represented the inexhaustible mental power of the security agency, which is one of the main bulwarks upholding the isolationist regime.

Many senior party and state officials were present at the performance with heir Kim Jong-un heading the list of attendees.

North Korea has been moving to anoint Jong-un, the incumbent leader's third and youngest son, as its new leader. Kim Jong-il took over power when his father died in 1994.

The younger Kim, believed to be in his late 20s, holds the rank of full general and was made vice chairman of the Central Military Commission of the ruling Workers' Party last year in an apparent step toward making him the country's next leader. (Yonhap News)