North Korea's leader Kim Jong-il and his youngest son and heir apparent, Kim Jong-un, have reviewed a military parade in the country's capital Pyongyang.

Swiss-educated Kim Jong-un, who is believed to be about 27 years old, has hardly ever been seen in public.

Little is known about the man who was made a four-star general last month and has been given senior government positions. Being the grandson of late "eternal" President Kim Il-sung, he would carry the Kim dynasty rule into a third generation.

Sixty-eight year old current leader Kim Jong-il is believed to be of poor health and thought to be preparing his son for his future role.

North Korea's 24 million citizens were able to watch Sunday's appearance live on state television.

Thousands of troops from every branch of North Korea's military goose-stepped around the plaza and applauded their leader.

Meanwhile, North Korean defectors and human rights activists protested against the North Korean leadership near the demilitarised zone separating the two Koreas.