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One of two longtime colleagues of Liberian President Charles Taylor (search) will assume power in the war-ravaged country within the next ten days, when the embattled leader insists he plans to make good on his promise to cede power in the face of fast arriving peacemakers.

Either House Speaker Nyundueh Monkomana or Vice President Moses Blah is expected to take over the reigns on Aug. 11, the day Taylor said he will officially resign from the post he has held since 1997.

"I will step down the morning of Aug. 11," insisted Taylor. "And the new guy will have to be sworn in by midday," he added, while avoiding the subject of whether or not he planned to act on neighboring Nigeria's (search) offer of asylum or leave the region that same day, as he has previously promised.

Late Saturday, the Bush administration jumped into the fray, with White House spokesman Scott McClellan stating, "Charles Taylor needs to leave. And we need to see it in his actions, not only in words."

Through it all, Taylor continued to stress that he will stand by his word. "The most important thing is, everything that we have said about resigning and leaving will happen," he said.

Speaking amid the backdrop of constant and booming gunfire being exchanged between government and rebel factions, Taylor shook hands with the envoys he welcomed to his lavish mansion along the Atlantic Ocean, before waving a hand toward the journalists:

"Get them out," he uttered.

Led by Mohamed Ibn Chambas (search) of West Africa's regional leaders bloc, the envoys brought Taylor a clear and succinct message: Leave Liberia as promised, when peacekeepers arrive.

West African heads of state, in a summit late last week in Ghana (search), committed to sending peacekeepers Monday to Liberia, where rebels pressing a 3-year-old war to oust Taylor have held Liberia's capital under two months of deadly siege.

Taylor must leave by Thursday, three days after the deployment, the West African leaders said — an unusually forceful message to a peer, delivered under strong U.N. and U.S. pressure.

A war-crimes suspect wanted by a U.N.-backed court in neighboring Sierra Leone (search), Taylor is blamed in 14 years of conflict in Liberia, a nation founded by freed American slaves in the 19th century.

Since the June 4 announcement of the war-crimes indictment, Taylor has pledged repeatedly to step down, only to hedge or renege on his promises. His recent statements include a declaration that he will leave as soon as the first peacekeepers arrive.

Taylor evaded the top-level regional delegation when it arrived Friday, sending a message instead that he had left Monrovia (search) for the country's second front, at the southeastern port city of Buchanan.

His spokesman told The Associated Press that Taylor's duties as military commander in chief, and the work Taylor was doing toward his own departure, had kept the Liberian leader from Friday's scheduled meeting.

"A man as popular as him, leaving the country will take a lot of groundwork," spokesman Vaanii Passawe said. Asked if Taylor was laying that groundwork, Passawe said, "Yes."

The envoys — Chambas, and government ministers of Nigeria, Ghana and Togo — were told Taylor would meet with them instead Saturday.

Taylor's nonappearance Friday had sparked rumors he had left the country, heightening tensions in his capital.

Fighting accompanying the two months of rebel offensives has killed well over 1,000 civilians in Monrovia. Hostilities have cut off the port and the main water plant, leaving the city of more than 1.3 million residents and refugees desperately short of food and water, and falling prey to cholera.

Heavy fighting broke out again Saturday at Monrovia's port, where rebels are battling to cross bridges toward downtown, the heart of Taylor's government.

Government fighters crouched midway along the two bridges at the port Saturday, directing heavy grenade and gunfire toward buildings at the other side — apparently, aiming at rebel snipers.

Black smoke rose from the rebel-held port. It was unclear whether the cloud came from fighting in the streets around the port, government shelling toward rebel positions, or other causes.

West African leaders have pledged to deploy at least 300 Nigerian forces on Monday, to be followed days after by troops of Ghana, Senegal and Mali. West Africans have called for a total of 5,000 regional peacekeepers.

The U.N. Security Council (search) approved deployment of the multinational force on Friday. The deployment is to last two months and will be followed by U.N. peacekeepers.

The Associated Press contributed to this report.