Kim Jong-il, the mercurial North Korean leader who ran one of the world’s most secretive governments, has died.

Kim, who was said to be 69 years old, died on Saturday following a heart attack, a weeping state media presenter announced two days after his death.

The state media constructed a cult of personality around him, but he was vilified by foreign governments for his oppressive rule and nuclear ambitions.

Kim had long been speculated to have been in ill-health and was rumoured to have suffered a stroke in August 2008.

This was the reason he assigned a number of important government and party positions to his third son and heir-apparent, Kim Jong-un, last year.

The reclusive "Dear Leader", as he was known, took over the reins of power in 1994 after the death of his father, the "Great Leader" and founder of North Korea, Kim Il-sung.

Kim never became the North Korean president, a role reserved for his father, who, despite his death, continues to hold the title of North Korea's "Eternal President".