Zimbabwe marks the 27th anniversary of its independence from Britain today.

President Robert Mugabe and 30,000 of his supporters have been celebrating during a party at a stadium outside Harare.

However, public celebrations across the country were expected to be muted because of political tensions and the country's mounting economic problems.

President Mugabe, who has been in power since 1980, marked the day with new threats against opposition forces he accuses of trying to topple his government on behalf of Zimbabwe's former colonial master.

During his speech, he accused the Zimbabwean opposition of trying to create a state of anarchy.

He said he had no problem with a 'legal, home-grown, peaceful and constructive political opposition,' but said chief opposition leader Morgan Tsvangirai, who says he was cheated of victory in presidential polls in 2002, was a 'pathetic puppet' of Britain and the US.

Last month, a prayer meeting in Harare attended by opposition leaders and activists was broken up by police leaving two people dead.

Scores of activists, including Movement for Democratic Change (MDC) leader Morgan Tsvangirai, were arrested and assaulted in police custody.

Southern African leaders have appointed South Africa President Thabo Mbeki to mediate between Mr Mugabe and the MDC party.

Currently, Zimbabwe's unemployment rate is 80%, inflation is nearing 2,000%, and 80% of their 13 million people are living below the poverty line.

Robert Mugabe's critics say he has plunged the country into crisis but the 83-year-old president says the disaster is because of economic sanctions imposed by the West.

Last month, the International Monetary Fund condemned Zimbabwe's government saying its failure to deal with the country's mounting economic problems would result in more hardship and rising political tension.

It also forecast that inflation could hit 5,000% by the end of the year if President Mugabe's government did not act swiftly.