Johannesburg - Zimbabwe's prime minister-designate Morgan Tsvangirai was shuttling between African capitals Friday in an attempt at winning the hearts and minds of regional leaders ahead of a crisis summit on Zimbabwe that finally promises some tough talking.

Tsvangirai was due to travel to Namibia and Malawi on Friday and Angola on Saturday to canvass their support ahead of the emergency Southern African Development Community (SADC) summit in Johannesburg on Sunday, senior sources in his Movement for Democratic Change (MDC) said.

On Thursday, Tsvangirai met with South African President Kgalema Motlanthe and ruling African National Congress (ANC) leader Jacob Zuma, the sources said. Tanzania, Comoros, Mauritius and Seychelles have also been part of the charm offensive.

President Robert Mugabe was also trying to curry support, telling US president-elect Barack Obama he was "ready to engage" with him, in a departure from his usual anti-US rhetoric.

South Africa, which chairs the 15-nation SADC grouping, has promised to take "quite a hard stance" with the Zimbabwean leaders at the summit.

Motlanthe and Zuma are considered more sympathetic to the opposition than ex-leader Thabo Mbeki, who is both a close ally of Mugabe and SADC's mediator in the conflict.

The summit will try to pressure Mugabe and Tsvangirai into implementing the power-sharing agreement they struck on September 15.

That deal, which allows Mugabe to remain president and makes Tsvangirai prime minister of a government of national unity, is on the brink of collapse, mainly because they cannot agree on the distribution of cabinet posts.

While past SADC summits on Zimbabwe have been relatively toothless, the patience of southern Africa with the disputing parties now appears to be wearing thin.

"As far as I'm concerned SADC must make those Zimbabweans reach an agreement," Zuma told reporters in Cape Town Thursday. "They must force them.

But MDC members say they have little faith the promises of tough talking mean SADC is about to get tough with Mugabe, not them.

The hero of the 1970s war against British rule still commands wide respect on the continent, despite presiding over his country's economic collapse.

Sounding increasingly pessimistic about sharing power, the MDC said Thursday a fresh spate of attacks by state forces and arrests of its members had "killed the dialogue."

The MDC says openly it believes the solution lies in fresh presidential elections. Botswana's President Ian Khama has echoed that call, but Mugabe's party is virulently opposed.

Mugabe placed second to Tsvangirai in the last credible presidential elections in March.

To ensure victory in a second round of voting in that election in June, his supporters and state forces terrorized MDC supporters, killing scores of them in a campaign of retribution that led Tsvangirai to pull out of the run-off.

While the MDC is lobbying for another vote, most Zimbabweans see power-sharing as the only way of quickly restoring stability, a precondition for attracting much-needed aid and investment.

Around 3 million Zimbabweans are in need of urgent food aid but Western governments, under pressure to turn around their own economies, are balking at putting money into Zimbabwe in the absence of a credible government.

The United Nations World Food Programme, which is feeding over 1 million Zimbabweans, launched an urgent appeal for 141 million dollars in early October to sustain its operations.

By Thursday, WFP spokesman Richard Lee told Deutsche Presse- Agentur dpa, only Venezuela had come to the table - with 750,000 dollars. (dpa)