Syria will not use chemical or other unconventional weapons except in the case of a foreign attack, foreign ministry spokesman Jihad Makdissi said on Monday.
"Syria will not use any chemical or other unconventional weapons against its civilians, and will only use them in case of external aggression," Makdissi told a media conference in Damascus.
"Any stocks of chemical weapons that may exist, will never, ever be used against the Syrian people," he said, adding that in the event of foreign attack, "the generals will be deciding when and how we use them."
Fears have been rising that President Bashar al-Assad's regime might be prepared to use the country's arsenal of chemical weapons in the repression of a 16-month insurgency after reports his stocks were being moved around the country.
The statement came a day after the US said it would "hold accountable" any Syrian official involved in the release or use of the country's chemical weapons.
Neighbouring Jordan's King Abdullah II also said that in the event of a descent into all-out war, chemical weapons could fall into the hands of 'extremists', including certain rebel groups.