African leaders hoped to find a resolution to Zimbabwe's deepening political crisis Saturday at an emergency summit in Zambia, but state media reported that President Robert Mugabe would not attend the "unnecessary" meeting.

Instead, South African President Thabo Mbeki, a key mediator in the crisis, traveled to Harare to meet Mugabe before the summit, Mbeki's spokesman Mukoni Ratshitanga said. Mbeki's motorcade was seen speeding from the airport toward Mugabe's offices Saturday morning.

Official results from the March 29 election have yet to be released. Independent tallies suggest Mugabe lost, but garnered enough votes to force a runoff. Opposition leader Morgan Tsvangirai says he won outright and has traveled the region asking neighboring leaders to push for Mugabe to resign after 28 years in power.

The opposition says Mugabe is using the delay in announcing results to send ruling party militants and security forces into the countryside to wage a campaign of violence to intimidate opposition supporters before a possible runoff.

On Friday, police banned all political rallies, a move that appeared designed to foil opposition plans to take to the streets of Harare to ratchet up the pressure on the regime.

International pressure on Mugabe has been growing as well since the election. In his strongest warning to Mugabe yet, British Prime Minister Gordon Brown said the world's patience with Zimbabwe's regime is "wearing thin."

The southern African leaders' meeting in Zambia could also add pressure on Zimbabwe to release the results. However, previous meetings of regional leaders expected to criticize Mugabe have instead ended with statements of support for him.

The state-run Herald newspaper reported Saturday that Mugabe would not attend the summit.

The paper quoted the foreign affairs secretary, Joey Bimha, as calling the summit "unnecessary" because the country's electoral commission was still collating results of the presidential vote.

Bimha said he and three Cabinet ministers will represent Zimbabwe at the summit instead. Mugabe's spokesmen and Zambian officials previously said the Zimbabwean president planned to attend, but Mugabe's representatives started to suggest Friday he might back out.

It is a rare move by Mugabe, who has regularly appeared at regional and international meetings despite international condemnation of his administration.

Mugabe has traditionally enjoyed the support of other African leaders, using past meetings of the Southern African Development Community to denounce his opposition and Western leaders he accuses of plotting to topple him.

Saturday's emergency regional summit was called by Zambian President Levy Mwanawasa, the only southern African leader to publicly criticize Mugabe's policies. At least 10 heads of state were expected, Zambian Information Minister Mike Mulongoti said.

They will meet as Zimbabwe's opposition says a government crackdown on them is worsening.

In an interview from Botswana on Friday, Tsvangirai implied he feared returning home, saying he was a "prime target" for security forces.

Tsvangirai arrived in Lusaka on Friday night with spokesman Nqobizitha Mlilo, who called for "a final solution" from southern African leaders who have notably failed to criticize Mugabe.

"Surely it must now weigh upon them that they need to find a final solution," Mlilo told The Associated Press. "Zimbabweans went to the polls, voted for change, voted for the MDC and Mr. Tsvangirai. The democratic will of the Zimbabwean people must be protected by the leaders of southern Africa."

Tsvangirai's Movement for Democratic Change has held no major protests since the vote, but party officials had planned a rally Sunday, a day before an expected High Court ruling on their petition to force the release of the results.

Party leaders would decide Sunday whether to defy the ban on political rallies, and call for a general strike, MDC spokesman Nelson Chamisa said.

Ruling party officials had encouraged militants to invade the country's few remaining white-owned farms, saying they were trying to protect Zimbabweans from encroaching colonialism. Opposition officials say such attacks are a smoke screen for assaults on mainly black opposition supporters.

International human rights groups say they have received reports of dozens of politically motivated attacks, widespread enough to suggest a coordinated program of retribution.