Rebels in the Central African Republic are warning that they could enter the capital Bangui soon, despite their agreement with the government to hold unconditional talks early next month.

On Sunday, the streets of the capital were largely empty and residents said they were stockpiling food in the face of a possible rebel onslaught.

The rebels' threat comes three weeks after they began their uprising. In that time, they have seized control of about one-third of the country and have forced the C.A.R. military to retreat to Damara, the last major town on the way to Bangui, about 75 kilometers away.

African Union chief Thomas Yayi Boni is expected to travel to the C.A.R. to meet with President Francois Bozize in a bid to to start the peace talks with Seleka, an alliance of three armed groups.

The rebel coalition accuses Mr. Bozize of failing to honor a 2007 agreement that included provisions that its fighters would be reintegrated and paid after laying down their arms in a previous uprising.

Late last week, the United States temporarily shut down its C.A.R. embassy and began evacuating staff. The United Nations also evacuated non-essential personnel from the country because of the threat of violence.

The C.A.R. won independence from France in 1960. About 250 French troops are in the country as part of a peacekeeping mission.

Some in the C.A.R. have called on France to do more to counter the rebel threat, but French President Francois Hollande says he only wants to protect his country's interests and nationals, not to intervene in the affairs of the former French colony.