The United States on Tuesday said it wanted evidence on the use of chemical weapons in Syria after the French said there was evidence sarin gas had been used, dpa reported.
White House spokesman Jay Carney noted the French report said more work needed to be done to establish who had used the chemical weapons, in what quantities they were used and under what circumstances.
"We need to expand the evidence we have, we have to make it reviewable, we have to have it corroborated," he said. "We will continue in that effort."
The US was working with its allies and the Syrian opposition to investigate the use of chemical weapons in order to get information that could be used to make policy decisions, he said.