French President Francois Hollande on Sunday blamed the regime of Syrian President Bashar al-Assad for an alleged chemical attack near Damascus and vowed France would not let the attack "go unpunished", dpa reported.
Hollande said there was "a range of proof" indicating that the attack involved chemical weapons and that "everything led to believe the Syrian regime was responsible," the presidency said after a telephone call between the French leader and Australian Prime Minister Kevin Rudd.
Hollande expressed "France's determination to not let this act go unpunished."
He also spoke with British Prime Minister David Cameron. The two leaders agreed to hold talks soon on "what responses to make to this intolerable act," the presidency said.
The Syrian opposition said at least 1,300 people were killed in toxic gas attacks by al-Assad's forces on rebel strongholds on Wednesday. The government denied the allegation.
Medicines Sans Frontieres has said three hospitals in Damascus had reported that some 3,600 people showed "neurotoxic symptoms" within three hours of the bombardment.
French Foreign Minister Laurent Fabius, on a visit to Jerusalem Sunday, called on the international community to agree on a strong response to the incident.
"I have already spoken clearly about the use of chemical weapons and Assad's regime. We must respond strongly to these events," he told reporters.