PARIS, July 24 (Xinhua) -- French Foreign Minister Laurent Fabius on Tuesday stressed that an Arab League proposal of a safe exit for Syrian President Bashar al-Assad would not save him from punishment.

"In the end, for him ... there will be no impunity ... Al-Assad will fall, it is only a matter of time," France's top diplomat told the state-run television France 2.

On Sunday, Arab foreign ministers proposed to al-Assad and his family members a safe exit if he quits power, a move strongly rejected by the Syrian government, slamming it as "flagrant interference" into the country's internal affairs.

Fabius also said the use of chemical weapons by Syrian forces was "unacceptable" after Damascus acknowledged it had such arms that could be used in case of "foreign aggression."

"Any use of chemical arms is completely unacceptable. (U.S.) President (Barack) Obama made statements to this effect and so have others... These weapons are under strict surveillance by the international community," the French minister noted.

Last week, armed rebels seized control of sections of Syria's borders and killed several of al-Assad's closest military allies in an attack against intelligence compound in Damascus, a move that escalated fighting in the capital. Enditem