In a phone conversation on the eve of Foreign Minister Jean-Yves Le Drian's trip to Tehran, the two presidents agreed to work together in the coming days with the United Nations, Damascus and other countries who are involved to improve the situation for civilians and make a ceasefire effective.
France also expects Iran to make a "constructive contribution" to solving crises in the Middle East, the presidency statement said.
Violence has escalated in eastern Ghouta, despite a U.N. ceasefire call a week ago and the bombing of the besieged Syrian enclave represents a "simply unacceptable" punishment of civilians, the United Nations said on Sunday.
Le Drian also said that Iran needed to address concerns over its ballistic missile programme or risk new sanctions.
Iran said France's concern over its ballistic missile programme was "wrong", the semi-official Fars News agency said.