ISIS can be eradicated in Syria and Iraq, hopefully by the end of the year, according to French defence minister Jean-Yves Le Drian.
Speaking to France Info radio on Thursday, Le Drian said that conditions are "in the process of coming together" to defeat ISIS.
"I note that Daesh (Islamic State) is retreating and that Daesh is retreating significantly," said Le Drian.
"Since Daesh's occupation of Syria and Iraq, since the attempt to attack Baghdad in June 2014, I think Daesh has lost between 30 and 40 per cent of its territory."
An international coalition is providing air support to Kurdish and Iraqi forces, which intend to liberate Mosul, in Iraq, and Raqqa, in Syria, by the end of the year, the minister added.
"We will need... a lot of determination, but I think the conditions are in the process of coming together for eradicating Daesh," he said.
"For the first time, I have this slightly optimistic message."
ISIS took over Raqqa in Syria in early 2014 and then seized Mosul during an offensive in June that year.
The atrocities performed by the jihadist group toward Christians, Yazidis and other minorities are increasingly widely being labelled genocide. The House of Commons voted unanimously to lable it genocide on Wednesday, though the Conservative government refused to support the motion.
The European Parliament passed a similar motion in February, and the US secretary of state John Kerry declared ISIS was "genocidal" in March.
Additional reporting by Reuters
