French President Emmanuel Macron has said that he will order strikes in Syria if there is "proven evidence" that President Bashar Assad's government used chemical weapons against civilians.

Macron told reporters on Tuesday evening France "will strike the place where they are launched or where they are prepared."

He acknowledged that French intelligence services don't have the necessary proof to this day that "chemical weapons banned by the treaties have been used against civilian populations."

Since the beginning of the year, there have been some reports of suspected chlorine attacks in Syria — including at a rebel-held town in February where several were treated for breathing problems.

France said chemical analysis of a deadly sarin gas attack in Syria last April bore "the signature" of Assad's government.