The Federal Opposition has called on the Government to officially recognise Morgan Tsvangirai as the President of Zimbabwe.

Coalition foreign affairs spokesman Andrew Robb says Robert Mugabe has been exposed as a brutal, illegitimate tyrant.

Mr Robb says all independent analysts believe Mr Tsvangirai won the necessary 50 per cent of the vote in the March election.

He says Mr Rudd should act decisively and recognise Mr Tsvangirai as the rightful president and encourage other nations to do the same.

Mr Robb says Australia is not doing enough.

"In Opposition, Mr Rudd talked about hauling Mugabe before the International Criminal Court, making Zimbabwe one of Australia's top five policy priorities and he even warned the Chinese Government about propping up the Mugabe regime," he said.

"So Mr Rudd could be urging all countries, including China, to recognise Mr Tsvangirai and in turn to see some real pressure on the UN to act."

AU summit

Meanwhile Mr Mugabe has arrived at an African Union (AU) summit in Egypt where his fellow African leaders are expected to urge him to reach a power-sharing agreement with the opposition.

The summit in the resort of Sharm El-Sheikh is expected to be dominated by the question of how to respond to the discredited run-off election that returned Mr Mugabe to power.

Tanzanian Foreign Minister Bernard Membe says that rather than debating whether Mr Mugabe should be addressed as President, delegates will be focusing on how to help the Zimbabwean people.

"It's not the matter of the titles of a person who determines security and is the built-in Africa. It's the way forward," he said.

"We are in a serious business here. The question is the people of Zimbabwe - what do we do for the suffering people of Zimbabwe?"

- ABC/BBC