Assad staying in power would be 'grotesque error': Macron

French President Emmanuel Macron said today that a "return to normal" in Syria that left its leader Bashar al-Assad in power would be a "grotesque error", in comments seemingly directed at his Russian counterpart Vladimir Putin.

"We can see those who would like to return to normal as soon as the war against Daesh (the Islamic State group) is finished: Bashar al-Assad would stay in power, the refugees... will return and Europe and few others would help with reconstruction," Macron said.

But "such a scenario would be a grotesque error", he added. After coming to power in May last year, Macron shifted French policy towards prioritising the destruction of the Islamic State group rather than ousting Assad, warning of a "failed state" if the leader were forcibly removed.

But he has previously called the Syrian leader an "enemy of the Syrian people" who should ultimately face a war crimes court.

Macron's latest comments during a major foreign policy address to French ambassadors appeared to be a rebuke to Putin, who is Assad's biggest backer. On August 18, Putin called on Europe to financially contribute to the reconstruction of Syria to allow millions of refugees to return home.

After more than seven years of brutal war, Macron warned in Monday's speech that Assad was on the verge of creating a fresh humanitarian crisis in Idlib province.

The regime says it is determined to retake the northwestern province on the Turkish border -- Syria's last major rebel stronghold -- amid speculation of a looming Russian-backed assault.

"The situation is alarming because the regime is threatening to create another humanitarian crisis in Idlib province and until now has shown no desire to negotiate the slightest political transition," Macron said.

"This means reinforcing pressure on the regime and its allies, and I expect Russia and Turkey to take account of their roles and the commitments they have made," he added.

"Since day one I have considered Daesh to be our principal enemy, and I have never made the ousting of Bashar al-Assad a condition of our diplomatic or humanitarian action in Syria," he said.

But he accused Assad of "creating thousands of refugees" and "massacring his own people".