Foreign secretary Jack Straw has condemned president Mugabe's efforts to retain "power at all costs" following his victory in Zimbabwe's elections.

Commonwealth and Southern African Development Community observers are expected to reject the poll as having "failed to meet key, broadly accepted criteria".

Results show Mugabe to have secured 1,634,382 votes - substantially more than the 50 per cent needed for victory - while opposition candidate Morgan Tsvangirai received 1,170,590 votes.

International observers have condemned Zimbabwe's presidential election after Robert Mugabe secured a controversial fifth term in office.

Responding to the result, Straw said: "For months the government of Zimbabwe has conducted a systematic campaign of violence and intimidation designed to achieve one outcome - power at all costs. It is no surprise that this outcome has now been achieved."

He said that president Mugabe had been responsible for preventing voters from registering, ordering the police to break up rallies, had and cutting the number of polling stations in opposition strongholds.

"We will be consulting our friends and allies in the European Union, the United States and the Commonwealth," said Straw.

The foreign secretary will be making a statement in the Common on Thursday, by which time he hopes to have received the report from the Commonwealth observers.

The Conservatives have condemned Mugabe and called on the government to take action against his regime.

"The murder, torture and intimidation which have been in evidence for the last few months have all clearly been designed to rig this election,'' said shadow foreign secretary Michael Ancram.

"The British government should begin immediately to build a coalition with the objective of seeing democracy restored in Zimbabwe and Mugabe's evil and corrupt regime removed."

Amnesty International has said it is alarmed about the conduct of the elections.

"We are deeply concerned for the safety of those arrested in the light of the well-established pattern of 'disappearances,' cruel, inhuman and degrading treatment by Zimbabwean security forces,'' an Amnesty spokesman said.