JOHANNESBURG, South Africa President Robert Mugabe faced deeper international isolation Wednesday, with African states demanding that a discredited runoff election be postponed and anti-apartheid icon Nelson Mandela rebuking the Zimbabwe leader for the first time.
Tougher sanctions, sporting bans and economic boycotts could be next and world support may build for opposition leader Morgan Tsvangirai, who called Wednesday for talks on power sharing.
Regional heads of state from southern Africa met in Swaziland and said Friday's runoff should be postponed until conditions permitted a free and fair vote.
President Bush said the runoff election appears to be a "sham," joining the international condemnation of Mugabe's actions.
At least 300 Zimbabwean opposition supporters, meanwhile, were seeking refuge at the South African Embassy in Zimbabwe. Ronnie Mamoepa, a spokesman for the South African Foreign Ministry, said the ambassador was talking with the group and that the situation was under control.
In London, Mandela made a carefully worded but pointed attack on Mugabe, saying there has been a "tragic failure of leadership in our neighboring Zimbabwe."
The speech, at a fundraiser that included Prime Minister Gordon Brown and former President Bill Clinton, was the first time the former South African president has spoken publicly about the political crisis in Zimbabwe. His words are devastating for Mugabe and will weaken his claim to be a champion of African interests.
Although out of office for nearly a decade, Mandela remains a commanding and respected figure. He uses his influence sparingly, and it is particularly rare for him to publicly differ with South Africa's current president, Thabo Mbeki. South Africans and other Africans have been increasingly questioning Mbeki's leadership on Zimbabwe, so Mandela's brief but sharp comments will have particular resonance.
For Mugabe, they are a rebuke from a leader he sees as a fellow freedom fighter, and will be hard to dismiss or ridicule so often Mugabe's response to criticism.
Tsvangirai made the call for peacekeepers in a commentary published Wednesday in the British newspaper The Guardian. Asked about it at a news conference later in Harare, Tsvangirai said: "What do you do when you don't have guns and the people are being brutalized out there?"
He stressed he was not calling for military intervention.
Queen Elizabeth II stripped Mugabe of his knighthood, acting on the advice of her Foreign Secretary David Miliband, who has pointed to widespread violence and intimidation of Zimbabwe's opposition ahead of the runoff in which Mugabe is the only candidate. Scores of opposition activists, including high-ranking party members, have been attacked or killed since the first round of the election in March.
Mugabe was made an honorary knight in 1994, when he was considered an anti-colonial hero. The queen's move put him in the company of the late Romanian leader Nicolae Ceausescu, who had his title taken away in 1989 at the height of his nation's revolution.
Bush called upon the African Union to continue to highlight the "illegitimacy" of the elections and keep reminding the world that the process is "not free and it's not fair."
Bush said the people of Zimbabwe deserve better.
"The people there want to express themselves at the ballot box, yet the Mugabe government has refused to allow them to do so. This is not just and it is wrong," he said.
Brown's spokesman Michael Ellam said sanctions against the southern African country are under review, but said Britain wanted to guard against hurting the population.
"We are mindful of the humanitarian impact on Zimbabwe, but we would not want to see anything that would prop up the regime in any way," Ellam said.
European Union leaders last week threatened Zimbabwe with more, unspecified sanctions. Brown said then that could include more targeted sanctions against members of Mugabe's regime.
EU nations already have an arms embargo in place against Zimbabwe in addition to a suspension of development aid and an assets freeze and travel ban against Mugabe and more than 100 other top government officials.
The England and Wales Cricket Board severed all bilateral ties with Zimbabwe's cricket authorities after Brown insisted the team should be banned from entering Britain. Earlier, Cricket South Africa imposed sporting sanctions on Zimbabwe.
In South Africa, which has strong economic ties with Zimbabwe, there are increasing calls to try to force Mbeki to take a tougher stand. Some ask whether a country seen as appeasing a dictator should be hosting the 2010 soccer World Cup. South Africa could face a public relations disaster similar to what China has faced over Tibet as it prepares to host the Olympics.
The South African government has trod softly around Mugabe during Zimbabwe's recent political crisis because of his credentials as a fighter against colonial rule.
The head of South Africa's African National Congress Jacob Zuma said this week that the situation in Zimbabwe is out of control but it was one of the few times a senior South African politician has openly criticized Mugabe.
Companies with Zimbabwean links are under pressure. After British media raised questions about its mining interests in Zimbabwe, Britain's Anglo American issued a statement expressing "deep concern" and condemning violence there.
Robert Rotberg, director of Harvard's Kennedy School program on Intrastate Conflict, said that while sanctions and boycotts may not convince Mugabe to loosen his grip on power, they are sure to sway public opinion and possibly change the minds of top military leaders.
Without his security apparatus and their intimidation tactics, Mugabe's power "could vanish overnight," Rotberg said.
Neighboring countries could "effectively bottle Mugabe up" by banning Zimbabwean aircraft from flying over their airspace and curtailing electricity deliveries to the landlocked country, he said. The U.N., AU and Southern African Development Community could then push him aside to take over during a transitional period until they can ensure a free and fair election.
"Tightening the noose will make the people around Mugabe realize that this ship is really sinking, and they should get off," he said.
In a measure of the continuing tension, Tsvangirai returned to the Dutch Embassy in Harare following his news conference. Tsvangirai first fled to the embassy on Sunday following his announcement he was withdrawing from the runoff. He sought refuge after getting a tip that soldiers were headed to his home.
At his news conference, Tsvangirai urged African leaders to guide negotiations to end the crisis with a political settlement, with the goal of forming a coalition transitional authority in Zimbabwe.
He said discussions could not begin until there was an end to attacks on his supporters. Tsvangirai also wants a release of "political prisoners," including his No. 2, Tendai Biti, who has been jailed since earlier this month on treason charges that can carry the death penalty.
Zimbabwean Deputy Information Minister Bright Matonga reacted with derision: "Is he out of his mind?"
Matonga said the government and Mugabe's ZANU-PF were focused on the election. Tsvangirai was to be on the ballot, electoral officials said Wednesday, saying his withdrawal came too late to be valid.
"There will definitely be elections on Friday," Matonga said.
Tsvangirai said he was asking the AU, whose heads of state hold a regular summit in Egypt next week, to take over mediation, which so far has been in the hands of Mbeki and a southern African regional group.
Tsvangirai had previously called on Mbeki to step aside, accusing him of bias toward Mugabe and saying his "quiet diplomacy" was not working. Mbeki has refused to publicly denounce Mugabe. Even after Tsvangirai spoke at his news conference, South African government spokesman Themba Maseko refused to refer to Zimbabwe as being in "crisis."