[…] American and European intelligence analysts now believe that President Bashar al-Assad’s troops have used chemical weapons against rebel forces in the civil war in Syria, an assessment that will put added pressure on a deeply divided Obama administration to develop a response to a provocation that the president himself has declared a “red line.”
According to an internal memorandum circulating inside the government on Thursday, the “intelligence community assesses that the Assad regime has used chemical weapons on a small scale against the opposition multiple times in the last year.” President Obama said in April that the United States had physiological evidence that the nerve gas sarin had been used in Syria, but lacked proof of who used it and under what circumstances. He now believes that the proof is definitive, according to American officials. […]
The conclusion by American intelligence agencies strengthens their assessment earlier this year and poses an important test for the White House.
Mr. Obama had repeatedly said the use of chemical weapons by Syrian forces would a cross a red line, but he has not indicated what action he would take in response.
In an April letter to Congress, the White House said that intelligence agencies had “varying degrees of confidence.”
But the conclusion of the latest intelligence review is much stronger and is based on evidence that includes reporting on planning by the regime for the use of chemical weapons, accounts of specific attacks and descriptions of physiological symptoms.
The draft statement notes there is no reason to think the resistance has access to chemical weapons.
“We believe that the Assad regime maintains control of these weapons, and has taken steps to secure these weapons from theft or attack,” it states. “We have no reliable, corroborated reported to indication that the opposition has acquired or used chemical weapons.”
According to a C.I.A. report, which was described by an American official who declined to be identified, the United States has acquired blood, urine and hair samples from two Syrian rebels — one dead, and one wounded — who were involved in a firefight with Syrian government forces in mid-March near the town of Utubya, northeast of Damascus.
The samples showed that the rebels were exposed to sarin and supports the conclusion that the regime has used the weapon.
In recent days, the British and French government have also asserted that there is evidence that the Assad regime has used chemical weapons.