Separately, government and opposition leaders say security forces have withdrawn from the southern city of Taiz, a flashpoint of anti-government protests. The Reuters news agency quotes an opposition leader as saying looting and other unrest have been spreading in the city since the forces pulled out.

The ongoing conflict between forces loyal to Mr. Saleh and anti-government rebels has led to to fears the country may be on the brink of civil war. Mr. Saleh has three times over the past several weeks defied an accord negotiated by the Gulf Cooperation Council to would end his 33-year reign.

Nearly 400 people have been killed since the popular uprising against Mr. Saleh began in January.