Robert Mugabe vows to live to 100, after reports he collapsed

However, speculation is mounting that the president's fast-deteriorating health is determining sudden shifts in his party's policy as his Zanu-PF party frantically pushes for early polls.

Two days after he reportedly collapsed at his Harare mansion, Mr Mugabe, 87, struck a defiant tone when he said he was a fitness fanatic who exercised daily.

"I fall sick if I don't exercise," he said. He said he took calcium supplements but did not use the "huge machines" his wife Grace favoured for her workouts.

In power for 31 years, Mr Mugabe has already made five trips this year to Singapore for medical attention. Each trip has cost almost 2 million.

Presidential spokesman George Charamba insists the trips were merely for a routine cataract operation. Grace Mugabe is also understood to have sought treatment for a dislocated hip.

"I am not old," Mr Mugabe insisted yesterday. "I am 87, but my body says the counting doesn't end at 87, at least you must get to 100."

But rumours that his health has taken a turn for the worse will be fuelled by a report that he collapsed at his mansion on Tuesday.

The Zimbabwe Mail, whose contributors are said to include state media reporters, claimed that aide Didymus Mutasa had rushed to Mr Mugabe's side and that his private medical team were summoned to revive him. The true extent of Mr Mugabe's health problems is a closely guarded secret, known only to a few top Zanu-PF officials. But claims he suffers from prostate cancer have been current for years. Ministers say that Mr Mugabe sometimes falls asleep in meetings or has to leave abruptly, raising suspicions his strength is ebbing.

Analysts claim that is why Zanu-PF is insisting elections to end the troubled coalition government be held this year - before Mr Mugabe dies. His rival, prime minister Morgan Tsvangirai of the Movement for Democratic Change (MDC) has said elections cannot be held before May next year.

But Zanu-PF spokesman Rugare Gumbo last week insisted that elections would be held this year and not in 2012 or 2013 as Mr Mugabe's chief negotiator Patrick Chinamasa had earlier agreed with South African negotiators.

"They're getting scared he might not make it to 2013 or 2012 for that matter," said political analyst Dr John Makumbe.

Experts claim that if the president dies while the coalition is still in place, parliament must sit to elect a successor from Mugabe's bitterly-divided party who will likely stay in power until polls are held.Zanu-PF hawks are worried that MDC legislators would side with a "moderate" figure such as vice-president Joyce Mujuru "who wouldn't be able to hold the factions together" leading to Zanu-PF's collapse, suggests Dr Makumbe.

But if the ailing leader wins an early poll, he will have the power to personally choose a successor to hand over to. "That person will then run the country for the next five years," says the University of Zimbabwe professor.

The president confirmed yesterday that the polls would go ahead before the end of the year. "We should not delay the process any further than is necessary," he said.

Tellingly, his allies are also worried about his health - though for different reasons. China is reported to be including a VIP medical facility in a military centre it is building in Christon Bank, near Harare. The facility would mean Mugabe could "import" an Asian doctor to be on standby for him, it has been reported. And South Africa's ruling African National Congress (ANC) party said this week that mediators had expressed concerns over what would happen if Mr Mugabe dies or steps down before a new constitution is in place. For now, Mr Mugabe is trying to dispel all rumours his health is anything but sound.

He was last seen in public on Saturday at the wedding of his farm manager's daughter, where he said a polygamous sect had given him a "holy" walking stick that made him irresistible to women.

"If I point it at a woman, she will love me instantly," he said.