Harare - Zimbabwe's former finance minister Simba Makoni received a major boost Friday in his bid to topple President Robert Mugabe when he won the endorsement of a rebel faction of the main opposition MDC party.

Arthur Mutambara, leader of a splinter grouping of the Movement for Democratic Change, told reporters Makoni was the only man with a realistic chance of beating Mugabe at national elections on March 29.

"Our political party has decided, in pursuit of the national interest, to endorse the presidential bid in Zimbabwe by Dr Simba Makoni," Mutambara said at a press conference in the capital Harare.

"We will not as a party be fielding a candidate for the presidency of this country for the elections being held on March 29, rather what we are going to do is to support vigorously throughout the country the presidential bid of Dr Simba Makoni."

Mutambara added he would be himself be contesting a parliamentary seat in Zengeza West, 30 kilometres (18 miles) south west of the capital.

The former student leader had a major falling-out with main MDC leader Morgan Tsvangirai two years ago over whether to contest lower house elections.

It had been expected that the pair would patch up their differences and agree on a joint platform before next month's joint parliamentary and presidential elections, but long-running talks broke up without agreement earlier this month.

Makoni threw his hat into the ring last week, declaring he would stand as an independent against Mugabe who has ruled the former British colony since independence in 1980.

Mutambara made no direct reference to Tsvangirai, who is also contesting the polls, but said Makoni had the advantage of appealing to disenchanted supporters of the ruling Zimbabwe African National Union - Patriotic Front (Zanu-PF) party as well as traditional government opponents.

"Dr Makoni is a courageous Zimbabwean. Makoni has the ability to unify people across the political divide and he has a strategic vision," said Mutambara. - Sapa-AFP