Iran's security chief has told President Bashar al-Assad that Syria is part of a vital regional alliance that Tehran will not allow to be broken.
During talks in Damascus, Saeed Jalili said Syria was an essential part of an axis of resistance.
The statement came a day after Syrian Prime Minister Riad Hijab defected to the opposition.
Syrian TV showed President Assad greeting Mr Jalili, his first TV appearance in two weeks.
President Assad was last seen on state TV on 22 July - four days after a bomb killed four security chiefs in Damascus.