Nigeria's opposition has warned country couldface a "massive revolt" unless newly re-elected President Olusegun Obasanjo resigns and permits a new round of voting.
Mr Obasanjo won a second term with 62 per cent of Saturday's vote, compared with 32 per cent for his leading rival, former junta leader Mr Muhammadu Buhari.
Some 20 parties, including Mr Buhari's, joined yesterday in demanding that Mr Obasanjo step down by May 29th, dissolve the country's election commission and quickly allow a new vote.
"If Gen Obasanjo fails to heed this humble advice being dished out to him, the consequence may be massive revolt," said Mr Olagbade Ogboro, chairman of a small opposition party, the National Action Congress, in reading the jointstatement.
The ultimatum renewed fears of violent protests after a weekend ballot that was regarded as more peaceful than expected. But international observers said the balloting was flawed by ballot-box stuffing and bribery in parts of the country.
Mr Buhari described the vote as the "most fraudulent Nigeria has held since independence". He said: "I hope there won't be violence . . . but if you impose a fraudulent government upon [people], I don't think they will accept it".
Mr Obasanjo said the vote was clean and that many Nigerians would see it as a "significant step forward in the history of elections in this country".
Critics of the one-time military ruler who became a civilian statesman say he has done little to fight poverty and corruption - his main promises before his first election in 1999.
AP