The latest showdown is due on August 16 when regional leaders meet in Luanda. The crucial SADC summit will urge Zimbabwe's suspension if Mugabe remains defiant.

SA broke cover this week in its diplomatic wrangle with Mugabe when President Jacob Zuma, speaking through his official spokesperson Lindiwe Zulu, made it clear Pretoria had finally lost patience with Mugabe’s increasingly oppressive regime.

In an interview after an outbreak of Zanu (PF) sponsored violence in Parliament, Zulu pledged to put Mugabe "on the spot" by urging a concerted drive against him.

Diplomatic sources said this could include a sanctions regime, halting aid and effectively kicking Zimbabwe out of SADC.

"The facilitator is not happy that we are remaining fixed on the same issues (violence)," Zulu said. "The facilitator is gravely worried by the violence, any violence from any quarter. We want to go to Angola with a progress report. It seems there is regression.

"We have been to Livingstone, Windhoek, Sandton and now Luanda and we are stuck with the same problem. The facilitator is not happy about this."

A SADC diplomat told The Zimbabwean: "The tragedy unfolding in Zimbabwe is driven by one man's ruthless campaign to hang on to power whatever the cost. He's destroying his country, damaging the rest of southern Africa and making wretched the lives of his people."

Zulu's attack will inflame the already combustible stand-off between Harare and Pretoria. He has been blamed by Mugabe's spindoctors for seeking to topple the veteran despot in what the regime calls a Western-inspired plot.

Pressure has been growing from human rights groups for SA to lead the way in a tougher stance against Mugabe, as human rights abuses continue unabated.

They include widespread torture and persecution of members of the MDC, a ruthless crackdown on freedom of the press and prevention of independent international observers at the election.

Sources said SA's attitude toughened after it became clear that Mugabe was going to ignore pleas for moderation. Introducing SA economic sanctions had been put on hold in the hope Mugabe would relent and allow the global political agreement to be fully implemented.

Diplomatic sources said Britain, whose leader David Cameron was in SA two weeks ago, was urging a sanctions programme that would force Mugabe to clear obstacles to a free and fair vote. There is acknowledgement in the UK that the Western targeted measures have been ineffective.

The House of Lords last week recommended a change in the Zimbabwe foreign policy. Mugabe and his henchmen find themselves faced with the real prospect of losing power at the next poll.

The MDC has some extraordinarily courageous people and overwhelming evidence of wide popular support. Mugabe's response has been to unleash the "war veterans" campaign to terrorise the political opposition.

The response of the SADC has been feeble indeed. The refrain from the club of dictators is that this kind of thing was to be expected in Africa. But Zuma has been a lone voice in the wilderness, flatly refusing to countenance Mugabe's arrogance.

By The Zimbabwean