Harare — Zimbabwe's state-owned Herald newspaper reported Saturday that the Nigerian leader, President Olusegun Obasanjo, is to visit President Robert Mugabe on Monday, the day after his inauguration, and on the eve of a special Commonwealth meeting to assess the disputed presidential election's results.

Obasanjo, along with President Thabo Mbeki of South Africa and the Australian prime minister, John Howard, are scheduled to meet in London on Tuesday to pronounce on whether the election was free and fair and whether any action should be taken against Zimbabwe.

The special Commonwealth 'troika' of Nigeria, South Africa and Australia was set up early in March after Britain and other Western nations failed to have Zimbabwe suspended from the 54-member Commonwealth. The compromise, agreed by consensus as is required in the Commonwealth, was that the special task force would report back to Secretary General Don McKinnon after the election.

But Obasanjo and Mbeki's role is key on another level. Most African observers of the election concluded that although there may have been problems, the poll was "legitimate". The Herald reported on Saturday that Mbeki had endorsed that view. The Nigerians already appeared to have come to that conclusion, after the Nigerian government delegation used the same language in their report.

Obasanjo and Mbeki, seen by Western governments and the G8 nations as Africa's leading representives, are now under considerable pressure to persuade Mugabe to form a national unity government that could include the loser of the presidential contest, the opposition leader of the Movement for Democratic Change, Morgan Tsvangirai.

But on Friday, Tsvangirai and the MDC's general secretary, Welshman Ncube, told journalists that there was no way they would join a Mugabe government. The MDC has rejected the outcome of the election, saying Mugabe robbed Tsvangirai of victory by manipulating the poll and intimidating and disenfranchising opposition supporters.

It is not known what precise form of national unity government is being proposed to Mugabe, but there are various alternative scenarios doings the rounds, including one in which Mugabe would step down after an agreed period, opening the way for a transitional administration, with or without Morgan Tsvangirai, and - eventually - new elections.

For now, the MDC position remains that Mugabe leads an illegitimate government and that, for progress to be made, he must step down.