Omran al Zoubi, Syria's information minister, charged an Islamist extremist group had used the internationally banned weapons, CNN reported Thursday.
Al Zoubi said the Syrian government "would never" use such weapons "if we had them."
"President Obama says chemical weapons are a red line," he said. "Then he is in direct accordance with President Assad who also thinks that chemical weapons are a red line."
Syria has denied it possesses or has used chemical weapons.
Obama has said the use of such toxins would be a "game changer" that could affect whether the world community becomes more involved in the conflict that has killed about 70,000 people.
The Syrian Network for Human Rights says it documented another 94 deaths on Wednesday. Those killed included nine children, eight women and 10 who died while being tortured.
Some 37 of the victims were killed in and around Damascus, SNHR said. Another 16 died in Hama and 15 in Aleppo.