A spokesman for the secretary-general at U.N. headquarters in New York confirmed the move after Annan had his monthly luncheon with members of the Security Council and U.S. Ambassador Anne Patterson.
Last month the team reported Syria apparently had withdrawn its 29,000 troops, but said it couldn't tell for sure about intelligence units because of the clandestine nature of their work.
Some officials suspect those intelligence units were responsible for the bombing assassinations of former Lebanese Prime Minister Rafik Hariri Feb. 14 and journalist Samir Qasir, an outspoken critic of Damascus, last week.
The U.N. Security Council last year had passed a resolution calling for all foreign forces to be withdrawn from Lebanon.