Robert Mugabe is engaged in a last-ditch and desperate bid to cling to power in Zimbabwe, Tony Blair has told MPs.

In a Commons statement, the Labour leader said Mugabe had made it impossible for Commonwealth observers to monitor the conduct of next week's general election.

"The violence and intimidation unleashed by president Mugabe in his desperation to prevent an opposition victory in next weekend's elections is totally unacceptable," he said.

"So is the way in which he made it impossible for EU observers to monitor next weekend's elections, obliging them to withdraw from Zimbabwe so that they could not document the abuses of the election campaign."

He said that there could be "no doubt" that "horrific acts of violence and intimidation" were taking place in the country.

Blair claimed that Mugabe was using the issue of land reform to undermine democracy in his country.

"His actions have now provoked a grave economic crisis in a country which has the potential to be rich and successful," he said.

The prime minister said there had been a "strong current of criticism" about Mugabe's actions at the Commonwealth summit, but said it was unrealistic to have expected agreement on proposals for expulsion.

"In a body representing over 50 separate nations there was no realistic prospect of a consensus for suspending Zimbabwe from Commonwealth membership in advance of the elections this coming weekend."

Change in tone

But before leaving Australia yesterday morning, Blair delivered a frank warning that the Commonwealth's credibility was on the line over the question of Zimbabwe.

"There is no point in using diplomatic language. We should have provided a far stronger statement and backed it up with action," he said.

He hit out at the decision to delay the imposition of sanctions against the Mugabe regime. Setting himself apart from other Commonwealth leaders, Blair said the final decision on Zimbabwe represented the "lowest common denominator".

Whilst he dismissed suggestions that the Commonwealth had split along black/white lines over the proposed action against Zimbabwe, he let it be known that the final decision was unacceptable.

"We postponed the day of judgment on Zimbabwe and I think that is the wrong thing to do," said the prime minister.

Australia's foreign minister, Alexander Downer, expressed concern that African countries has used the summit to close ranks behind Zimbabwe.

Helen Clark, the prime minister of New Zealand, also expressed frustration at the communiqué agreed by the Commonwealth heads of government.

"The communiqué reads a little like everyone is responsible for the violence and intimidation," she said. "That is not the case."