US intelligence agencies have assessed "with varying degrees of confidence" that Syria has used small amounts of chemical weapons, according to US Defense Secretary Chuck Hagel.
Mr Hagel told reporters in Abu Dhabi today that the White House has sent Congress a letter about the conclusion, which he said was reached "in the past 24 hours." He said the weapons may have included the nerve gas sarin.
“Varying degrees of confidence” is a term indicating that intelligence agencies hold conflicting views on the quality of the evidence.
"Intelligence assessments alone are not sufficient," the White House director of legislative affairs, Miguel Rodriguez, wrote in a letter to congressional leaders. "Only credible and corroborated facts that provide us with some degree of certainty will guide our decision-making."
Reuters