"For years we have trod a journey of hunger, pain, torture and brutality," he told reporters in his first public comments since Saturday's elections. "Today we face a new challenge of governing and rehabilitating our beloved country, the challenge of giving birth to a new Zimbabwe founded on restoration not retribution, on love not war."

The Zimbabwe Electoral Commission has yet to release returns from the presidential vote, but Tsvangirai insists he defeated President Robert Mugabe. And he denied reports that he was negotiating to ease out Mugabe, who has led the country from liberation to economic collapse over the past 28 years.

Tsvangirai said Tuesday he was waiting for an official announcement of the results before he would enter talks with Mugabe. But he asserted that he got more than the 50 percent simple majority needed for victory.

Mugabe, 84, has made no statement about the election.

Tensions rose as the days passed without an official announcement on the presidential vote, and some people stayed home from work. A senior police officer, Wayne Bvudzijena, went on state radio to say: "Our forces are more than ready to deal with perpetrators of violence."

Paramilitary police have stepped up patrols in the capital, Harare, and in Bulawayo, the second-largest city, and roadblocks have been set up at strategic entries to Harare. The opposition has most of its support in urban centers.

As Zimbabweans waited for the returns, "our country is on a precipice, on a cliff edge," said Tsvangirai, head of the Movement for Democratic Change.

In Washington, Gordon Johndroe, spokesman for the National Security Council, said "it's clear the people of Zimbabwe have voted for change. It's time for the Zimbabwean Electoral Commission to confirm the results we have all seen from the local polling stations and respected NGOs."

The Zimbabwe Election Support Network, a coalition of 38 Zimbabwe civil society organizations, said its random representative sample of polling stations showed Tsvangirai won just over 49 percent of the vote and Mugabe 42 percent. Simba Makoni, a former Mugabe loyalist, trailed at about 8 percent.

On Tuesday, a businessman close to the state electoral commission and a lawyer close to the opposition said aides to Tsvangirai and Mugabe were negotiating a graceful exit for the president. Both spoke on condition of anonymity because of the sensitivity of the issue.

However, Tsvangirai said "there are no discussions," adding, "let's wait for ZEC to complete its work."

The businessman said Mugabe has been told he is far behind Tsvangirai in preliminary results and that he might have to face a runoff. He said the prospect was humiliating for Mugabe, and that was why the president was considering ceding power.

The situation remained fragile and could deteriorate without a Mugabe resignation.

Martin Rupiya, a military analyst at South Africa's Institute for Strategic Studies and a former lieutenant-colonel in the Zimbabwe army, said he had heard of the military's involvement in negotiations for Mugabe to step down.

The election result "has compelled the military, the hawkish wing and the other moderate, to begin to reconsider accommodating the opposition," he said. "Because of the nature of the wins they have been forced to reassess."

Political analyst John Makumbe said he had learned from military sources that they would respect the results of the elections. Last week, security chiefs had warned they would not serve anyone but Mugabe and would not tolerate an opposition victory.

The Electoral Commission has released results for 182 of the 210 parliamentary seats—giving Tsvangirai's party 92 seats, including five for a breakaway faction, to 90 for Mugabe's ruling party. At least six Cabinet ministers lost their seats, according to the official results.

Zimbabweans fear that Mugabe may declare himself the winner, as he has in previous elections that observers said were marked by rigging, violence and intimidation.

Should he consider stepping down, he would have to weigh the concerns of those who have profited from his patronage, including military leaders, party officials and businesspeople. They have received mining concessions, construction contracts and preferential licenses to run transport companies and other businesses.

Marwick Khumalo, head of the Pan-African Parliament observer mission, told South African radio that leading members of Mugabe's party were contemplating defeat with trepidation.

"I was talking to some of the bigwigs in the ruling party and they also are concerned about the possibility of a change of guard," he said. "ZANU-PF has actually been institutionalized in the lives of Zimbabweans, so it is not easy for anyone within the sphere of the ruling party to accept that 'Maybe we might be defeated or might have been defeated.'"

At independence, Mugabe was hailed for his policies of racial reconciliation and development that brought education and health to millions who had been denied those services under colonial rule. Zimbabwe's economy thrived on exports of food, minerals and tobacco.

The unraveling began when Mugabe ordered the often-violent seizures of white-owned commercial farms, ostensibly to return them to the landless black majority. Instead, Mugabe replaced a white elite with a black one, giving the farms to relatives, friends and cronies who allowed cultivated fields to be taken over by weeds.

Today, a third of the population depends on imported food handouts. Another third has fled the country as economic and political refugees, and 80 percent have no jobs. Life expectancy has fallen from 60 years to 35, and shortages of food, medicine, water, electricity and fuel are chronic.

The economy is in dramatically worse shape than in past elections, with inflation now the highest in the world.

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