Macron told Putin in a phone conversation that "humanitarian access (should be) guaranteed as soon as possible, in particular in Eastern Ghouta where hundreds of thousands of people are in great distress," the president's office said in a statement.
A "de-escalation zone" deal agreed by regime allies Iran and Russia and rebel backer Turkey has been in place in the region near the capital Damascus since July. But humanitarian aid, subject to authorisation by the Syrian authorities, is only trickling in and hundreds of cases of severe malnutrition have been reported in recent weeks.
The region is one of the last strongholds of rebels fighting the regime of Syrian President Bashar al-Assad since 2011.
Macron also stressed "the need to renew the mandate" of investigators from the UN and the Organisation for the Prohibition of Chemical Weapons (OPCW) in the coming weeks, the statement said.
The UN panel known as the Joint Investigative Mechanism (JIM) issued a report -- disputed by Damascus and Moscow -- last month that blamed the Syrian government for a sarin gas attack in April.
"France will not give up on the fight against impunity and the full and complete dismantling of the Syrian chemical programme," the statement from the French president's office said.