Liberia's president, under heavy pressure to step down, rejected a Nigerian offer of safe haven in part because he fears it won't protect him from a war crimes indictment, senior U.N. diplomats told The Associated Press.

The United States has said it will be impossible to end a three-year civil war in Liberia while President Charles Taylor (search) remains in power. New fighting ravaged the capital Monrovia (search) last week before Taylor's forces claimed victory and th the U.N. diplomats, who spoke on condition of anonymity Tuesday, Taylor rejected the safe haven offer for several reasons, including uncertainty over whether the offer would shield him from the U.N. indictment he faces on war crimes charges.

"There are a lot of unanswered questioned here and so Taylor isn't willing to entertain the issue right now," one Security Council (search) diplomat said at U.N. headquarters in New York.

Taylor was indicted June 4 for allegedly backing rebels in Sierra Leone (search) who fought a 10-year terror campaign for the country's diamond fields. He has also been accused of playing a role in several other West African conflicts.

Taylor had offered in June to cede power as part of peace talks toward ending the Liberia insurgency, which has displaced more than 1 million people. He later retracted the offer, as he has done before, and said he will serve to the January 2004 end of his term. He even suggested he might run again.

The offer for Nigerian exile was negotiated with the help of a Security Council mission visiting the region. The delegation met with Nigerian President Olusegun Obasanjo over the weekend.

Under the deal, Nigeria wouldn't turn Taylor over to the U.N.-Sierra Leone court even if the indictment stands, diplomats in the region said.

The Bush administration, which has been asked to supply 2,000 peacekeepers to Liberia, might not accept that. U.S. diplomats at the United Nations have laid out three conditions for further discussion on Liberia: Taylor stepping down and turning himself over to the special court in Sierra Leone and a cease-fire the international community can support.

British Ambassador Jeremy Greenstock (search), who is leading the Security Council delegation, said he would leave it to Obasanjo to make public any details regarding the offer. But Greenstock noted that Nigeria has no extradition laws.

"We hope whatever choices are made in the region or anywhere else, impunity for those who commit gross abuses of human rights in any situation will not be allowed," Greenstock said in Ivory Coast. The delegation canceled a planned stop to Liberia for security reasons.

Secretary-General Kofi Annan stepped up pressure on Bush to take a lead role in restoring peace to Liberia, which was founded by freed American slaves in the 19th century.

"Many are expecting the United States to lead that operation. Several countries, members of the U.N. have appealed for that. The Liberian population is also asking for that," Annan said while traveling in Switzerland.

West African leaders have said they want an answer from the United States before President Bush arrives in Africa next week.

U.N. diplomats said Annan was frustrated that the Bush administration wasn't moving faster considering the grave situation on the ground.

Mere talk of Washington even considering such action set off celebrations in Monrovia, with thousands dancing and singing at the U.S. Embassy gates late Tuesday.

At the Vatican, Pope John Paul II expressed "deep sadness" Wednesday over fighting in Liberia and northern Uganda, and urged all possible efforts to help people in those nations live in peace and security.

"I appeal to all for a commitment" to end the violence from long civil wars in both nations, John Paul said at his weekly public audience. He urged the faithful there not to lose hope.