France called on Friday for a political transition in Syria that would not include Bashar al-Assad, after a series of shifting positions on resolving the six-year-old conflict.
"We cannot build peace with Assad," Foreign Minister Jean-Yves Le Drian said on French radio RTL.
"He cannot be the solution," said Le Drian, who was defence minister under the former Socialist government.
"The solution is to establish... a timeline for political transition that can lead to a new constitution and elections, and this transition cannot happen with Bashar al-Assad."
French President Emmanuel Macron said in June that the removal of the Syrian president was not a "prerequisite" for peace in the war-torn country, and that he did not see a "legitimate successor" to the leader who has been in power since 2000.
Paris had been a key supporter of the opposition to Assad's rule since the start of the conflict in 2011 which has since killed more than 400,000 people and displaced millions.
But Macron said that the fight against the Islamic State (IS) group was a priority for France, which has endured a string of terror attacks that have killed more than 230 people since 2015. Some of these were planned in Syria.
France's armed forces are in action as part of the US-led international coalition fighting IS in Syria as well as Iraq.
Le Drian said on Friday that IS "will be defeated in Syria," leaving the country with a "single conflict, that of the civil war" pitting an opposition against the Assad government.
Macron has tasked Le Drian with forming a new contact group on Syria to relaunch the stalled political process.
So far Paris has not been forthcoming on the composition of the group, notably on the question of whether regional power Iran - a key backer of the Syrian regime along with Russia - would take part.
Peace talks
A new round of talks on the conflict will be held in Astana on September 14-15, Kazakhstan announced on Friday, with key powers looking to shore up safe zones on the ground.
UN Syria envoy Staffan de Mistura has hosted seven rounds of largely unsuccessful talks in Geneva, with Assad's fate one of the main obstacles to progress.
The Syrian conflict began when the Baath regime, in power since 1963 and led by Assad, responded with military force to peaceful protests demanding democratic reforms during the Arab Spring wave of uprisings, triggering an armed rebellion fuelled by mass defections from the Syrian army.
According to independent monitors, hundreds of thousands of civilians have been killed in the war, mostly by the regime and its powerful allies, and millions have been displaced both inside and outside of Syria.
The brutal tactics pursued mainly by the regime, which have included the use of chemical weapons, sieges, mass executions and torture against civilians have led to war crimes investigations.