Morgan Tsvangirai, the Zimbabwean opposition leader, flew to Zambia today before a crucial summit of southern African leaders aimed at resolving Zimbabwe's political turmoil.

Levy Mwanawasa, the Zambian President, will host an urgent meeting of the Southern African Development Community (SADC) tomorrow to formulate a regional approach to the worsening situation. Mr Mwanawasa has been fiercely critical of the policies of President Mugabe, last year likening the country’s economy to “a sinking Titanic”.

In recent days, Zimbabwe’s political limbo has moved into violence, as gangs of Mr Mugabe’s loyalist thugs roam the country invading and destroying the few remaining commercial white-owned farms, while the military has been deployed to co-ordinate an intimidation campaign against opposition voters.

Mr Tsvangirai's opposition party, the Movement for Democratic Change (MDC), claims it won Zimbabwe's presidential elections on March 29 and accuses Mr Mugabe of delaying the results to orchestrate a run-off.

It has called on southern African leaders to force Mr Mugabe to step down before the violence worsens. “The lives of all pro-democracy actors are not safe,” Tendai Biti, the MDC secretary-general, said.

Mr Tsvangirai has travelled around Africa this week in an attempt to shore up support against the ageing dictator. On Wednesday, he saw the President of Botswana but it was yesterday's meeting with President Mbeki of South Africa that was the most crucial.

Mr Mbeki has previously advocated a policy of “quiet diplomacy” towards Zimbabwe, but that strategy has been criticised recently by allies in Africa and the West.

An MDC spokesman said today that the meeting with Mr Mbeki had “gone well” and that they were “cautiously optimistic” about the outcome. Mr Tsvangirai would be a full participant in tomorrow's summit, he added, reiterating that the opposition leader’s election win made him a “head of state”.

In Harare, the High Court is due to rule today on whether the election results must be made public.

According to his spokesman, Mr Mugabe “was eagerly waiting for the [election commission] to complete its ballot votes verification freely without any interference and without pressure not to release the results.”

“It is not true that the president nor Government is holding the Zimbabwe election results,” he said.

Bright Matonga, the deputy information commissioner for Mr Mugabe’s Zanu (PF) party, told CNN that he believed opposition politicians would be “cowards; if they did not contest a runoff”.

Unwilling to allow Mr Mugabe to slope off into retirement, those supporting him – including the military – have taken the reigns, unleashing an orchestrated campaign of terror against opposition activists, election observes an ordinary voters in an attempt to secure Mr Mugabe victory in a second-round poll.

White-owned farms were the first targets of the violence that insiders say is being co-ordinated by 200 handpicked military and intelligence officers loyal to the President.

Police have also arrested Mr Tsvangirai’s lawyer. Innocent Chagonda, who successfully defended Mr Tsvangirai from treason charges in 2004, was seized on charges related to a helicopter hired for the MDC.

He had apparently demanded that police release the aircraft, which had been confiscated, when he was arrested for “interfering with police work”, the opposition said.

The MDC said the arrest yesterday was part of a wider campaign to clamp down on the Opposition in the wake of the elections. “As a party we feel this is a sustained effort on the part of the authorities against people who assist the MDC,” it said.

“This is an onslaught which is not only happening in the rural areas, but even in the civil service as people who are perceived MDC supporters are being intimidated."

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