"Let it be known that we are in SADC (the Southern African Development Community) voluntarily. If SADC decides to do stupid things, let it be known that we can withdraw from SADC," President Robert Mugabe told a rally.

Speaking to DW, the Advocacy officer for Crisis in Zimbabwe Coalition, Nixon Nyikadzino, thinks the elections will not be credible and some Zimbabweans already view them as disputed.

“If you look at the voter registration and the inspection process, it simply shows you that the election has been manipulated," he said.

The regional bloc had pressed Mugabe to have the elections postponed in order to allow time for reforms to the electoral register and to the role of the military to be carried out.

Zimbabwe's constitutional court ruled on Thursday that the election would go ahead on July 31, despite Mugabe's request for a two-week delay. But far from being bowed by an apparent setback, a defiant Mugabe issued a fiery rallying call to supporters on Friday, as he endeavours to extend his 33-year rule.

Mugabe and his supporters

Addressing thousands of Zanu-PF supporters who turned up for his election campaign launch, Mugabe spiritedly urged them to vote for his party in tones that suggested he was fighting for political survival.

There are fears that the upcoming election in Zimbabwe will not be credible

"You are our soldiers. You have a battle to fight. Go into the battle well-armed. "Go into the battle with the full knowledge that there is a political enemy. This is a do or die struggle,” Mugabe told his supporters.

The Zanu PF election manifesto and campaign is based on the theme Indigenise, Empower, Develop and Create Employment,

Zanu PF leaders believe that indigenisation, which means increasing local participation in foreign-owned firms, together with the land reform programme it embarked on in 2000, will deliver the election victory they desperately need for survival.

Prospects for an opposition victory

For years now, victory has eluded the main opposition party, the Movement for Democratic Change (MDC), but this year could be a turning point for the party, which is exuding confidence.

"The people of Zimbabwe are ready for change. We have absolutely no doubt that Prime Minister Morgan Tsvangirai will be the next president of Zimbabwe," said Finance Minister Tendai Biti, who is one of Tsvangirai's main backers.

Tsvangirai has posed the stiffest challenge to Mugabe in his 33-year rule of the southern African nation, but failed to win in the last elections in 2008 which were marred by violence.

Morgan Tsvangirai's party is confident of victory

But Defence Minister Emmerson Mnangagwa, who backs President Mugabe, voiced confidence that his candidate would win.

"We as ZANU-PF are very confident of victory in the harmonised elections with President Mugabe because of the progressive policies that we have put across," Mnangagwa told journalists.

Mugabe, who at the age of 89 is Africa's oldest leader, wants to continue at the helm of Zimbabwe despite worries about his health and advanced years. He denied reports that he suffers from prostate cancer or other major health problems.

He says he has cataracts, and returned home from Singapore on Sunday from what his spokesman called a routine visit to an eye specialist.