Mugabe is seeking another five-year term to extend his 28-year rule of the once-prosperous southern African country.

Rivals say his re-election would be a disaster for Zimbabweans who are suffering amid an economic meltdown, highlighted on Thursday when Zimbabwe said annualised inflation topped 66,000 percent in December -- a new record.

Millions of Zimbabweans are expected to vote in the presidential, parliamentary and municipal polls. Mugabe and his opponents have described the event as a landmark election in the country's post-independence period.

"We're very confident of victory, 99.9 percent confident," Emerson Mnangagwa, a cabinet minister and official with the ruling ZANU-PF party, told reporters after presenting Mugabe's election registration papers to a court in Harare.

The opposition is concerned the elections will not be free. Mugabe has been widely accused of rigging the last three major elections and of using security forces to quell dissent.

Earlier this week Mugabe, who turns 84 next week, told state media that he was "raring to go" into the election.

But Mugabe, who was described as a "discredited dictator" on Thursday by U.S. President George W. Bush, must contend with Simba Makoni, a renegade former finance minister who is running for president as an independent.

The ZANU-PF expelled Makoni, 58, earlier this week after he announced what many observers consider the most serious challenge to the veteran Zimbabwean leader, who has been in power since independence from Britain in 1980.

Makoni, accompanied by his wife, filed his registration papers at the court in Harare on Friday.

Morgan Tsvangirai, the leader of the main faction of the Movement for Democratic Change, the country's largest opposition party, also filed on Friday to contest the presidential election, although he did not do so in person.

The leader of a smaller faction of the MDC has pulled out of the race and is expected to back Makoni.

Makoni's entry could split the opposition vote and spur Mugabe's re-election in spite of the nation's economic misery.

Critics say government mismanagement has plunged the country into a crisis that is marked by soaring poverty, widespread malnutrition and chronic food and fuel shortages.

Mugabe says the problems are the result of sabotage by Western powers who are opposed to his policy of seizing white-owned farms and redistributing the land to blacks.

Despite accusations of widespread human rights violations, Mugabe is regarded in much of Africa as an anti-colonial champion and hero of the liberation era of the 1960s and 1970s.