As U.S. soldiers expanded their role in Haiti, rebel leader Guy Philippe said on Wednesday that his forces would lay down their arms.

"Now that there are foreign troops promising to protect the Haitian people ... and they have given the guarantee to protect the Haitian people ... we will lay down our arms," Philippe told a news conference.

Philippe's announcement comes as U.S. marines began protecting fleeing government officials from armed rebels in the island's capital.

Witnesses said the marines blocked access to a building at the Port-au-Prince airport.

Those who took refuge inside it were reportedly members of deposed president Jean-Bertrand Aristide's Lavalas party.

At the airport, U.S. Marine Corps Staff Sgt. Timothy Edwards said his mandate now included protecting Haitians from "reprisal attacks." That marked an escalation of his original orders, which were to protect American citizens and property.

Marines began arriving in the country shortly after Aristide fled on Sunday and 400 of them were expected to be in the country by mid-week.

Col. Dave Berger told a news conference foreign troops would increase their presence throughout the country.

However, the French and Americans who currently make up the United Nations-authorized peacekeeping force do not have orders to disarm Haitians, Berger added.

"We are not a police force," he said.

Port-au-Prince remained chaotic on Wednesday, as armed rebels continued to roam the streets.

There were reports of at least one fierce gun battle in a slum neighbourhood controlled by Aristide supporters.

Halfway around the world, Aristide remained sequestered on Wednesday at the presidential palace in the Central African Republic.

The former leader has charged that he was forcibly removed from power by the United States, a charge that U.S. officials deny.

Aristide's allegations have complicated efforts to find a permanent home. Some countries are reportedly concerned that accepting him would sour their relations with the U.S.

The Central African Republic's foreign minister said the deposed leader was comfortable in his temporary shelter.

"Aristide really likes to read" and has slept a lot, said Charles Wenezoui.

"We're about to give him a television and satellite dish so that he can monitor news around the world."