Meanwhile, the mandate of the U.N. observer mission that had been tasked to monitor Annan's six-point peace plan, which included a failed ceasefire, ends on Sunday.
But Lt. Gen. Babacar Gaye, the mission's head, told reporters the United Nations will maintain a presence after the 300 military observers and the other personnel depart.
"We will continue the search to move from violence to dialogue," Gaye said.
The U.N. Supervision Mission began monitoring a ceasefire agreed to by the government and rebels in April. But it never took hold, and violence soon surged.
Even though the mission has been criticized as ineffectual, Gaye said it has an "important legacy."
"At the end of the day we have paved the way for a united agreement by the Security Council for the United Nations to stay in this country for the search of peace and ending violence," he said.