The stage has been set for a presidential run-off in Zimbabwe after the ruling party, led by President Robert Mugabe, agreed to a second round.

An official from Mugabe's party, ZANU-PF, also said they would contest the results of 16 parliamentary seats, accusing Morgan Tsvangirai's opposition of bribing electoral officials.

"We agreed to have a rerun at a date to be set by" the electoral commission, said ZANU-PF Party Secretary and Minister of State Didymus Mutasa at a news conference Friday.

The announcement came after a five-hour party meeting, the first since results from the weekend election showed that it had lost control of the parliament.

According to Zimbabwe's law, a run-off must take place no more than 21 days after the first round of voting. But diplomats in Harare said Mugabe is planning a 90-day delay and a security crackdown.

Earlier on Friday, opposition leaders said Mugabe has "unleashed a war" in an effort to stay in power. The remarks came after authorities raided opposition party offices and foreign reporters were taken into custody.

The latest developments are an ominous sign, says Gabriel Shumba, a Quebec spokesperson for the Zimbabwe Exiles Forum.

"The will of the people may be subverted," he told Canada AM Friday morning.

He said news indicating that paramilitary groups are being armed could mean the status quo may subvert democratic results.

This past week's developments should concern Ottawa, Shumba noted. He said what happens in Zimbabwe has regional and global consequences.

Shumba said repression in the country has forced refugees to flee to neighbouring countries, and that could destabilize the region as a whole.

The Movement for Democratic Change, led by Tsvangirai, claims their candidate handily beat Mugabe in last week's election, but they are willing to engage in the run-off vote to decide the final outcome.

"Mugabe has started a crackdown," MDC secretary-general Tendai Biti told The Associated Press. "It is quite clear he has unleashed a war."

On Friday, about 400 veterans of Zimbabwe's independence war marched through Harare, the capital city. There are fears the demonstration by Mugabe loyalists may indicate he may use violence to stay in power.

Mugabe was once considered a national hero after he helped end white minority rule in his country in 1980. But despite his fight for independence, he has faced national and international criticism since 2000 for seizing white-owned farms, a move which appears to have led to an economic freefall.