As a young man he was the chubby playboy. In middle age he was a portly bon viveur. At his latest public appearance yesterday Kim Jong Il, the supreme leader of North Korea, was deathly — a scrawny, gaunt, almost skeletal figure whose appearance can only add to international anxiety about the future of the world’s most isolated nuclear state.

The skin hung slack around his jaws and neck and he walked with the limp that was in evidence at his last public appearance — the opening of North Korea’s tame parliament in April.

It was clear then that Mr Kim had suffered an episode of severe ill health, apparently a stroke in August that removed him from public view for months. To judge from the pictures — the only hard source of information about him — his health has since taken a drastic turn for the worse.

The images, from North Korean television, were of a ceremony to mark the 15th anniversary of the death of Mr Kim’s father, Kim Il Sung, the founding President of North Korea.

Mr Kim was pictured bowing before a vast crowd of party officials and military officers at the Pyongyang Indoor Stadium; earlier he was reported to have visited his father’s mausoleum at the Kumsusan Memorial Palace, where his embalmed body lies in state beneath a glass coffin.

The South Korean intelligence agency has reported signs that Mr Kim is paving the way for his youngest son, Kim Jong Un to succeed him.Unconfirmed reports have even had the 25-year old visiting Beijing to get to know officials of the closest thing North Korea has to an ally — China.

All year Pyongyang has staged a series of verbal and physical provocations, including the launch of an intercontinental rocket and an underground nuclear test, which suggest that it has abandoned expectations of negotiation with the international community in favour of whipping up nationalist fervour at home.

There are no obvious signs are that Kim Jong Il is in anything less than complete control but close examination of recent internal developments leads many Pyongyang-watchers fear to the conclusion that he appears to be preparing for a transition of power and leaning towards military hardliners instead of the more reform-oriented advisers he favoured earlier.

Any transition will only succeed with the help of the military. In his absence, the only power that will count may be that of raw military force.

The country’s notional head of state, Kim Yong Nam, told the gathering: “We will sternly smash the US imperialist forces and South Korea’s puppet regime. We will achieve the historical mission of national unification by realising; Kim Il Sung and Kim Jong Il’s policies.”

Times Recommends

• Should Knox’s trial even have reached the courtroom?
• 'Was it real?' The US bailout nightmare
• Iranian opposition plays the long game