A White House spokesman said on Tuesday that more evidence is still needed regarding the use of chemical weapons in Syria.

"As the president made clear, we need to expand the evidence we have, we need to make it reviewable, we need to have it corroborated before we make any decisions based on the clear violation that use of chemicals would represent by the Syrian regime," White House spokesman Jay Carney said at a briefing.

Carney's statement came after French Foreign Affairs Minister Laurent Fabius earlier the day confirmed the use of the fatal nerve agent sarin against Syrian rebels during the country's long and bloody conflict.

In response to the French conclusion, Carney said that this is "entirely consistent" with previous American assessment.

"We have made clear that we believe that if chemical weapons were in fact used in Syria, they were used by the Assad regime," he told reporters. "We are highly skeptical of claims that the opposition used chemical weapons."

"I think that it is essential, and I think the American people expect, that we take that evidence and we build on it and we build on it until we know what we have and we can present it," Carney said. "And that's what the president is insisting we do."

U.S. President Barack Obama had said evidence has pointed to the use of chemical weapons inside of Syria. He has called time and again the use of or failure to secure chemical weapons by the Syrian government a "red line" or "game changer" in his handling of the conflict in the Middle East country. But Obama has also made it clear that he needs more specific information about what has exactly happened there. Endi