Turkey and Qatar have agreed to requests from Tehran for help in seeking the release of 48 Iranians in Syria, kidnapped by an armed group in Damascus after visiting a religious shrine.
The rebels reportedly say some were not pilgrims but members of Iran’s revolutionary guards.
Meanwhile President al-Assad’s forces have again pounded rebel positions in Syria’s second city Aleppo.
Planes and artillery have been used, while thousands of troops surround the city. It is thought the government is preparing for a major assault.
The rebels have been showing off rockets and the odd tank they have confiscated, but mostly they are taking refuge behind the walls of buildings along the deserted streets.
Members of the Free Syria Army say they have been trying to keep order in areas they control.
There have been some complaints that rebels have used law and order as a pretext to impose religious law and mistreat people they don’t like.
In Damascus government forces say they are back in control of all areas after pushing the rebels out of their last strongholds.
But the claims are difficult to verify. On Saturday shelling and gunfire were heard in one district after government forces had stormed it.