Gen. Abdulsalami Abubakar's mission, announced Friday, comes on the heels of Annan's announcing he will reevaluate plans to send a U.N. military observer mission to Congo because of the crumbling cease-fire and a propaganda campaign against U.N. peacekeepers.
His moves and the council's statement reflect growing concern, dismay and frustration over the two-year war in Congo, which has dragged in five other countries and affected many more.
The United States has laid the blame squarely on Congolese President Laurent Kabila's government. So has Annan, though without naming him directly.
The Security Council issued a statement Friday underscoring "the lack of progress" in implementing last summer's cease-fire and "the deteriorating humanitarian situation."
The mandate of the U.N. mission in Congo is set to expire Aug. 30 and Annan asked the council to extend it until Sept. 30 so he can reevaluate the U.N. role. The United States introduced a draft resolution Friday that would extend the mandate until Oct. 15.
Abubakar will leave for the region in the next few days "to make clear once more" to the Congolese government the Security Council's demand for a cessation of hostilities, for freedom of movement for U.N. troops, and for its participation in an inter-Congolese dialogue aimed at forming a broad-based government, U.N. deputy spokesman Manoel de Almeida e Silva said.
While the United Nations was focusing on the situation in Congo in New York, the Congolese government ordered the expulsion of two U.S. diplomats, and a U.N. staff member sent to assess damage from fighting in the town of Kisangani was found dead in his hotel room.
The U.S. Embassy's press and political officers were ordered out for making statements the government claimed were inconsistent with their diplomatic role, the U.S. State Department said.
Fighting in Congo started in 1998 when rebel forces backed by Rwanda and Uganda tried to oust Kabila, who had support from Angola, Namibia and Zimbabwe.
The Rwanda-Uganda alliance fell apart after they backed rival rebel groups and the two countries turned their guns on each other in June in Kisangani.
Under last summer's peace agreement, 5,537 U.N. observers were to be stationed in Congo to supervise a cease-fire and the withdrawal of foreign forces. So far, only 264 U.N. military observers and about 15 international staff have been deployed.
By EDITH M. LEDERER