Zimbabwe President Robert Mugabe looks set to move forward with forming a government if opposition leader Morgan Tsvangirai does not sign a power-sharing deal on Thursday.

"If after tomorrow (Thursday), Tsvangirai does not want to sign. We will certainly put together a cabinet. We feel frozen at the moment," Thursday's edition of the The Herald quoted Mugabe as saying on his return from Zambia late Wednesday.

Power sharing talks between Mugabe and Tsvagirai, who heads the Movement for Democratic Change (MDC), were deadlocked in mid-August over Mugabe's desire to retain control of the country's security forces, according to the opposition.

Last ditch attempts to revive the negotiations by South African president Thabo Mbeki, who is mediating in the crisis, last week failed.

"We are a government and we are government that is empowered by elections. We should form a cabinet. We would not allow a situation where we will not have a cabinet forever," Mugabe told The Herald.

Several media reported that Mbeki was expected in Zimbabwe on Thursday as part of the negotiations, but his spokesman denied the reports.

"The president is not going to Zimbabwe," Mbeki spokesman Mukoni Ratshitanga said, adding however that the power-sharing talks were continuing.

MDC spokesman Nelson Chamisa also said that he was not aware that anything was planned for Thursday in Harare.

Mugabe and Tsvangirai put aside their differences briefly on Wednesday when they both attended the funeral of Zambian president Levy Mwanawasa in Lusaka.

According South African daily Business Day, Mbeki, who was also at the service, spoke with the Zimbabwean rivals there.

An earlier power-sharing deal put forward under Mbeki proposed that Tsvangirai become prime minister and Mugabe retain the presidency in an inclusive government.

But Tsvagirai said Wednesday that he had rejected the deal because Mugabe would keep his control over the security forces.

The deal would have seen economic and social ministries report to the prime minister and security ministries answering to the president, including the army and police which Tsvangirai said Mugabe had used to "brutalise" people.

On Thursday the MDC stressed that it would not react to Mugabe's apparent ultimatum.

"(Mugabe's party) ZANU-PF are trying to force us to swallow poison, we are not going to sign anything that does not put the people of Zimbabwe first," spokesman Chamisa told AFP.

"Mr Mugabe must be prepared to give some of his powers to Mr Tsvangirai. This is the last chance for Mr Mugabe to see the light for the people of Zimbabwe as he has not shown any form of seriousness to give up some of his powers," he added.

Zimbabwe's crisis intensified after Mugabe's re-election in a widely condemned June presidential run-off in which he was the only candidate.

Tsvangirai boycotted the election despite finishing ahead of Mugabe in the March first round, citing rising violence against his supporters.

Power-sharing talks began after both sides signed a memorandum of understanding on July 21.

Tsvangirai has repeatedly said he would not agree to any power-sharing deal that would not give him real political power.