A statement on May 23 by the New York-based Elie Wiesel Foundation for Humanity, and signed by 49 Nobel winners, said a "lack of legitimacy" on the part of the new national government "increases prospects for violent conflict with serious consequences for Nigeria and the region."

The Nobel winners are urging that a conference of national unity involving Nigerian religious, civil, business and political leaders be convened to mediate a crisis prompted by the recent vote. They are also urging that new elections be called within 18 months.

"Bogus elections raise serious questions about the new government's legitimacy," said Elie Wiesel, a human rights activist and Holocaust memoirist. "The best way to prevent violent conflict is through electoral reform and a new ballot."

Political violence has become increasingly common in Nigeria, despite the end of military rule in 1999. The April elections have caused further turmoil, with opposition candidates saying the election was rigged by outgoing President Olusegun Obsanjo's ruling party.

The Nobel winners said their recommendation is being "offered in all responsibility, to help consolidate Nigeria's transition to democracy after decades of military dictatorship. It is made without prejudice to potential legal recourse by aggrieved candidates."

The declaration by the Nobel winners came as the European Parliament on May 24 called on the European Union to halt any further financial assistance to the Nigerian government, until new balloting occurs.

Other Nobel laureates signing the statement included the writers J.M. Coetzee of South Africa and Wole Soyinka of Nigeria.