Liberia has formally asked Nigeria to extradite former Liberian President Charles Taylor.
Charles Taylor promised Liberians he would return
A spokeswoman for Nigerian President Olusegun Obasanjo said he would put the request to other African leaders.
A UN-backed war crimes tribunal in Sierra Leone wants to put Mr Taylor on trial for backing Sierra Leone rebels.
He stood down as Liberian leader and went into exile in Nigeria in 2003 under an international deal to end Liberia's 14-year civil war.
Liberian Information Minister Johnny McClain told the BBC that if the request was granted, Mr Taylor would be sent straight to Sierra Leone.
The 15,000 United Nations peacekeepers in Liberia are under instructions to arrest Mr Taylor and transfer him to the Special Court for Sierra Leone if he sets foot on Liberian soil.
A spokeswoman for the court's chief prosecutor Desmond de Silva told the BBC's Focus on Africa programme that he welcomed the news that Mr Taylor may soon end his exile in Nigeria.
"His cell is empty and awaiting his arrival," the spokeswoman said.
An official from Mr Taylor's National Patriotic Party said the news was "shocking".
1989: Launches rebellion
1991: RUF rebellion starts in Sierra Leone
1995: Peace deal signed
1997: Elected president
1999: Lurd starts rebellion to oust Taylor
June 2003: Arrest warrant issued
August 2003: Steps down, goes into exile in Nigeria
Mr Obasanjo has always refused to send Mr Taylor to Sierra Leone, saying he would only extradite him following a request from an elected Liberian leader.
Ellen Johnson-Sirleaf took power in Liberia in January after winning last year's elections and visited Nigeria earlier this month.
Mrs Johnson-Sirleaf has previously said her priority is rebuilding Liberia, rather than putting Mr Taylor on trial.
But before she briefed the UN Security Council in New York on the situation in Liberia, she confirmed the request, reports the AFP news agency.
"I asked the African (Union) leadership to bring the Taylor issue to closure," she said.
Mr Taylor is accused of selling diamonds and buying weapons for Sierra Leone's Revolutionary United Front rebels, who were notorious for hacking off the hands and legs of civilians during a 10-year war.
He also started the Liberian civil war in 1989, before being elected president in 1997.
Mr Taylor's supporters have said that he enjoys immunity from prosecution under the peace deal which saw him step down.
But human rights activists have accused him of breaking the terms of that deal by trying to influence Liberian politics.
Just before Mr Taylor stepped on a plane to take him to the south-eastern Nigerian city of Calabar in August 2003, he told Liberians: "God willing, I will be back."