Zimbabwe's opposition leader on Saturday accused President Robert Mugabe of preparing a "war against the people" and said the party was reluctant to take part in a presidential runoff election.

Movement for Democratic Change leader Morgan Tsvangirai stopped short of threatening a boycott but said a runoff was unnecessary. His party claims he won 50.3 percent of the vote in last weekend's election, but official results have not been released.

Tsvangirai said his party was reluctant to take part in a second round because of what he said was a mounting climate of fear.

"ZANU-PF is preparing a war against the people," Tsvangirai told a news conference. "In the runoff, violence will be the weapon. It is therefore unfair and unreasonable for President Mugabe to call a runoff."

On Friday, the ruling ZANU-PF party said Mugabe would fight to retain his 28-year grip on power in a runoff.

Independent projections show Tsvangirai won the most votes but not the 50 percent plus one needed for an outright victory.

Opposition officials said the party would launch a new court bid Sunday to force the commission to publish the results, after armed police prevented lawyers from entering the court on Saturday.

There is mounting international pressure on Zimbabwe to announce the presidential results. But South African President Thabo Mbeki, who was last year appointed mediator in Zimbabwe, urged patience.

"It's time to wait," Mbeki told journalists as he arrived for a meeting near London of government leaders hosted by British Prime Minister Gordon Brown. "Let's see the outcome of the election results," said Mbeki, who says quiet diplomacy is preferable to public criticism.

Tsvangirai said the violence and intimidation would likely worsen and appealed to African leaders and the United Nations to intervene to "prevent chaos and dislocation."

Deputy Information Minister Bright Matonga dismissed the comments.

"It's a lot of nonsense. Zimbabwe held a very peaceful election. There was no violence. Nobody was killed," he told Sky Television.

The law requires a runoff within 21 days of the first elections. But diplomats in Harare and at the United Nations said Mugabe was planning to declare a 90-day delay to give security forces time to clamp down.

On Friday, feared veterans of the guerrilla war who were used in the past to beat up opponents marched through the capital. Opposition party offices have been raided and armed police in full riot gear have detained foreign journalists.

Mugabe, 84, has ruled since his guerrilla army helped bring about an independent Zimbabwe in 1980. But his popularity has been battered by an economic slide that followed the often-violent seizures of white-owned commercial farms since 2000 that has this former food exporting nation dependent on international handouts. A third of the population has fled the country and 80 percent is jobless.

With inflation raging at more than 100,000 percent, authorities introduced a new bank note denominated at 50 million Zimbabwe dollars Friday. It's worth $1 on the widely used black market and buys just three loaves of bread.

"Mugabe must accept that the country needs to move forward," Tsvangirai said. "He cannot hold the country to ransom. He is the problem not the solution."

But he also held out an olive branch, saying he would welcome dialogue with Mugabe. He said his party would not revenge on Mugabe for any crimes committed during his rule.

"Please rest your mind, the new Zimbabwe will guarantee your safety," he said.

Tsvangirai tried Thursday to reassure security chiefs who vowed a week ago to serve no one but Mugabe, according to a person close to the opposition leader. But an agreed meeting with seven generals was canceled when the officers said that they had been ordered not to attend and that they would be under surveillance, according to the person, who requested anonymity because of the issue's sensitivity.

Tsvangirai urged Zimbabweans not to be cowed by fear.

"At this difficult moment, there comes a time when citizens take their destiny in their own hands and say 'No.' A time when we put aside fear and rise to the moment. They have spoken with one voice against the dictatorship," he said.