The UN Security Council has for the first time unanimously condemned violence against opposition supporters in Zimbabwe and said a free and fair presidential election is impossible now.
As international pressure mounted on President Robert Mugabe, Senegalese President Abdoulaye Wade and South African ruling party leader Jacob Zuma both called for postponement of the June 27th run-off.
South Africa, China and Russia, who have previously blocked discussion of Zimbabwe in the Security Council, joined in an unprecedented condemnation of the bloodshed after opposition leader Morgan Tsvangirai pulled out of the vote and took refuge in the Dutch Embassy.
International pressure has mounted on President Robert Mugabe
Mr Wade said Tsvangirai fled to the embassy after soldiers came looking for him at his home.
Mr Jacob Zuma, leader of South Africa's ANC, called for regional and UN intervention.
"The situation in Zimbabwe has gone out of hand, out of control... We cannot agree with what (the ruling) ZANU-PF is doing at this point in time," the African National Congress leader said at an investment conference.
Mr Tsvangirai has not requested asylum but spent a second night in the Dutch embassy last night. He told Dutch Radio 1 on Tuesday that his refuge was temporary and that the government had assured the Dutch ambassador that he would not be hurt.
Mr Tsvangirai said he could be ready to leave in the coming days.
He said President Robert Mugabe could no longer defy international opinion.
The 15-member Security Council echoed mounting international concern over Zimbabwe's political turmoil and economic meltdown, blamed by the West and the opposition on Mugabe, 84, who has held uninterrupted power for 28 years.
"The Security Council condemns the campaign of violence against the political opposition ahead of the second round of the Presidential elections scheduled for 27 June, which has resulted in the killing of scores of opposition activists and other Zimbabweans and the beating and displacement of thousands of people, including many women and children," the non-binding statement said.
Mr Tsvangirai told Dutch radio: "I think it's a very important resolution. It recognises the people who are accountable for the violence and it squarely placed that responsibility at Mugabe's leadership."
Mr Mugabe's government remained defiant and said the election would go ahead on Friday. The veteran leader accused former colonial power Britain and other Western countries of lying about the violence because they wanted to interfere.
The council's statement was watered down from an earlier British-drafted version, which explicitly blamed Mr Mugabe's government for the crisis and said Mr Tsvangirai would be the legitimate leader if a credible run-off vote could not be held.
But the final version said: "The Security Council regrets that the campaign of violence and the restrictions on the political opposition have made it impossible for a free and fair election to take place on June 27."
South Africa, an advocate of "quiet diplomacy" with Mr Mugabe, said it was "very pleased" with the statement because it "assists us in the mediation".
President Thabo Mbeki, the designated regional mediator in the crisis, has resisted calls to use Pretoria's powerful economic leverage over landlocked Zimbabwe.
But Mr Zuma, who now rivals Mr Mbeki as the most powerful man in South Africa, has become increasingly vocal over the crisis.