North Korean leader Kim Jong Un led a national memorial service Monday for his late father and predecessor Kim Jong Il on the first anniversary of his death, days after Pyongyang’s long-range rocket launch.

Kim Jong Il died of a heart attack on Dec. 17 last year, although his death was announced to North Koreans and the rest of the world two days later.

North Korean state television showed Kim and his wife Ri Sol Ju, who appeared to be heavily pregnant, paying homage at a national memorial service Sunday for Kim Jong Il in a mausoleum where the embalmed remains of his father lies along with those of his grandfather, the nation's founder Kim Il Sung.

Hundreds of thousands of people, civilian and military, were gathered outside the Kumsusan Palace of the Sun mausoleum in Pyongyang, during a three-minute silence observed across the nation, the AFP reported.

Kim's uncle, Jang Song Thaek, believed to be the effective second in command, and his aunt, Kim Kyong Hui, were seen attending a ceremony Sunday to inaugurate the renovated mausoleum, Reuters has reported.

The ceremony was broadcast live on state TV, with an emotional commentary by an announcer.

"Our people and the military are tearfully longing for the sunny smile of our dear father," the announcer said, the AFP reported.

"We yearn for you, and all the days we spent with you, with unendurable longing," she added.

However, the mourning was markedly upbeat, with the celebratory mood carrying over from last week's launch, Pyongyang's first successful use of a three-stage rocket to launch a satellite into orbit.

North Korea has tried five times to launch a satellite since 1998. An attempt to launch the Unha-3 rocket in April, as part of a celebration to mark the 100th birthday of the nation’s founder, Kim Il Sung, failed after about 100 seconds of powered flight.

The U.N. Security Council had condemned the launch, saying it constituted a test of a long-range missile technology that is banned under the U.N.'s resolutions.

The council warned North Korea — already subject to international sanctions for its 2006 and 2009 attempts to test a nuclear device — of possible measures in response as countries including South Korea and Japan pressed for stronger sanctions against Pyongyang.

At the mausoleum, Choe Ryong Hae, the military's top political officer, said North Korea should be proud of the satellite, calling it a show of strength to the world.