MONROVIA, Liberia ? Pressured by fellow West African leaders, President Charles Taylor promised Saturday to resign Aug. 11 after the expected arrival of peacekeepers, as his forces stepped up their battle against rebels for Monrovia’s port.

As fighting surged in the city outside, Taylor — after meeting with West African envoys — told reporters at his lavish oceanside executive offices that he would hand over power after a joint session of Liberia’s congress next week.

Taylor said he would step down the morning of Aug. 11 “and the new guy will have to be sworn in by midday.” But he refused to say when he would leave Liberia, as he has promised to do previously, and as West African leaders and the United States have demanded.

“The most important thing is, everything that we have said about resigning and leaving will happen,” said Taylor, who has been offered asylum by Nigeria.

Taylor has said he would hand power to one of two longtime colleagues — Nyundueh Monkomana, Liberia’s speaker of the house, or Moses Blah, his vice president.

The president had accused Blah of complicity in what he called a U.S.-backed coup attempt against him in June, but Blah eventually returned to what appeared to be his full public role. Monkomana is believed to be more acceptable to all sides, including rebels.

Taylor has been promising to surrender power since June 4, when a U.N.-Sierra Leone court announced a war-crimes indictment against him for his support of rebels there in a brutal civil war.

He also has made and broken other accords in 14 years of Liberian conflict.

Saturday’s meeting with regional envoys appeared to make at least some progress by committing Taylor to a specific date.

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

They had insisted that Taylor leave by Thursday, three days after the deployment — an unusually forceful message to a peer, delivered under strong pressure from the United States and United Nations.