The one-time military dictator now faces no further obstacles to taking office on 29 May - the date when General Abdulsalami Abubakar will stand down and bring to an end 15 years of military rule.

The challenge was brought by Olu Falae, the losing candidate in the 27 February presidential poll, but five judges in Nigeria's Court of Appeal dismissed it in its entirety because "it lacked merit".

Olu Falae: Allegations of corruption against his opponent

Speaking for Mr Falae's legal team, Solomon Asamota said the failed presidential candidate had directed them to take no further action.

But Mr Asamota criticised the decree under which the election was held, saying: "The decree was designed in a way that a petition against the election will definitely fail."

Allegations

Mr Falae had alleged that Gen Obasanjo:

• was a member of the Ogboni secret society and that this disqualified him for candidature
• benefitted from electoral fraud and bribery
• was ineligible to run for president because he had been convicted for treason

Mr Obasanjo's laywers argued that the charges were ambiguous, and not backed up by conclusive evidence.

Gen Obasanjo has embarked on a world tour to encourage international support for Nigeria in its transition to democracy.

Election observers have said there was evidence of widespread fraud in the poll, but that it did not affect the overall result of the election.

Gen Obasanjo was declared the winner of the election with approximately 63% of the votes.

Military man

He was Nigeria's military ruler before handing over to a short-lived democratic regime in 1979.

Gen Obasanjo was later convicted for treason for allegedly plotting against military dictator Gen Sani Abacha. He was pardoned last year after Gen Abacha's death, the coup plot is widely believed to have been invented by Gen Abacha to discredit his enemies.

Mr Falae filed his court challenge on the last permissible day under the election rules.