Thirteen members of a 32-strong team arrived from the Sierra Leone capital Freetown on board a Russian-built MI-8 helicopter that landed inside the US embassy enclosure, where they were met by US ambassador John Blaney.

They all wore bullet-proof vests.

The soldiers are part of a team which left the US naval base at Rota in southern Spain in the early hours of Monday on a mission to assess "the situation and determine whether further humanitarian assistance is required" in Liberia, Lieutenant Corey Baker had told AFP by phone earlier from Madrid.

"We'll take the team around to see different places where IDPs (internally displaced people) and refugees are. We are greatly concerned by the humanitarian situation," Ambassador Blaney said.

Among the 13 members who had arrived, one was a civilian who works for the Office of Federal Disaster and Relief Assistance, Blaney said.

Captain Roger Coldiron, the team's leader, said: "The rest of the team will be here today if the weather continues to cooperate."

He said: "I am not here to assess the military situation but I will assess the security situation" and determine humanitarian needs.

"We want that whoever will come will have a safe working environment," Coldiron added.

Washington is weighing up whether to send US peacekeeping troops to help end the latest civil war in Liberia, riven by almost incessant conflict since

US President George W. Bush, who is set to leave for a tour of Africa on Monday, has pressed Liberian President Charles Taylor to stand down as a first step to restoring stability and and bringing peace to Liberia.

Taylor accepted an offer of asylum from Nigeria on Sunday, but gave no indication when he would leave.

The embattled Liberian leader, whose troops have for four-and-a-half years been battling the rebel Liberians United for Reconciliation and Democracy (LURD), only controls around one-fifth of the country, as the rebels have pushed forward with their offensive to seize Monrovia and oust him.

Hundreds of thousands of Liberians have in recent weeks fled fighting on the outskirts of the capital to seek refuge in the heart of Monrovia, where many are living rough.

WAR.WIRE