Writing in an American newspaper, Mr Soyinka warned that the disintegration of Nigeria was now almost inevitable.

The Nobel Prize-winning writer said General Adusalam Abubakar had been in power for almost a month when Mr Abiola died, and could have released prisoners.

Wole Soyinka: called Abiola's death "a heinous crime"

Instead, he had chosen to keep Mr Abiola in captivity.

Traditional Muslim prayers for the late opposition leader passed off peacefully on Saturdayafter the security forces sealed off part of central Lagos to prevent a public ceremony.

Police banned the family of the late opposition leader Moshood Abioloa from holding prayers in his honour at a square in central Lagos.

Chief Abiola: his death sparked riots

The Lagos police chief, Abubakar Tsav, said the prayer meeting could be held at Chief Abiola's estate, but would not be allowed at the city's main square because of the risk of disturbances.

"We truly and most sincerely mourn the death of Chief Abiola and sympathise with the family but we will not allow thuggery and wanton destruction of life and property as experienced recently," he said.

BBC correspondents say followers of Chief Abiola had planned to gather in Tafewa Balewa Square to hold traditional Muslim prayers marking the eighth day since his burial.

Chief Abiola, the presumed winner of elections in 1993, died in detention on July 7 shortly before his anticipated release.

Dozens of people were reported killed in protests following the announcement of his death.

An international team of doctors reported that Chief Abiola died of natural causes, most probably heart failure.

However, many of the chief's relatives and followers believe he was murdered by Nigeria's military leaders.

Democracy plan awaited

Earlier on Friday, the new Nigerian military leader, General Abdulsalam Abubakar, held talks with the Secretary General of the Organisation of African Unity, Salim Ahmed Salim.

An official Nigerian statement afterwards quoted him as telling Mr Salim that the government was determined to give a hearing to all on the future development of the country.

An expected statement by General Abubakar on a transition to democracy is still awaited.

Local newpapers are reporting that Gen Akubakar will make a speech to the nation on Monday setting out his plans for a return to democracy.

The National Security and Defence Council has been meeting to consider proposals for a transition timetable drawn up by a committee appointed by General Abubakar.