The White House said on Tuesday that it was considering whether to intervene to halt fierce fighting in Liberia between rebel groups and the government of President Charles Taylor.
The White House also declared that it had not ruled out sending in US troops as part of an international peacekeeping force.
US President George W. Bush discussed the issue on Tuesday morning at a meeting of the National Security Council after several days of intense discussions involving the Pentagon and the State Department, administration officials said.
The White House later directed the Pentagon to refine the proposals being discussed, especially the possibility of having the US lead a peacekeeping force that would also draw from a number of African countries, military officials said. US Secretary of State Colin Powell spoke about Liberia on Tuesday with UN Secretary-General Kofi Annan, the State Department said.
Ari Fleischer, the White House spokesman, said the administration was "actively discussing what the next step should be" to help end the fighting in Liberia, a West African country that has had close ties to the US since its founding by freed American slaves in 1847.
Asked about American troops going to Liberia, Fleischer replied, "I'm not ruling it out."
The US has come under increasing pressure from the UN, Britain, France and West African countries to take a more active role in quelling the unrest.
Nigeria was considering offering Taylor asylum if he agreed to step down, though the terms of his possible departure were sure to be complicated by his indictment last month on war crimes charges by a court run by the UN and neighboring Sierra Leone.
US officials signaled they would be unenthusiastic about a deal that let Taylor escape prosecution.
"We support the court," Richard Boucher, the State Department spokesman, said.
In London, a member of Taylor's government told reporters that the Liberian leader, who was elected in 1997 after leading a long rebellion against the previous government, would agree to step aside only after a comprehensive peace deal was worked out.
"We look forward to working out details of an orderly exit of our government," Samuel Jackson, Liberia's minister of state for economic and financial affairs, said.
Annan told reporters in Switzerland that the situation demanded "a country with military capacity that can deploy a robust force -- it doesn't have to be very large -- that can make a difference on the ground and team up with West African forces."
With Bush scheduled to visit Africa next week for the first time as president, Washington appeared eager to avoid having him portrayed as standing by while Liberia degenerated further into violence.
Yet former administration officials said there was reluctance at the Pentagon to get involved in a complex and violent dispute that does not involve a compelling issue of national security, especially when American troops are already deployed in Iraq and Afghanistan.