The United States said Monday it was "highly skeptical" of an assertion that Syrian rebels had used chemical weapons, after a UN human rights investigator suggested the opposition had deployed sarin gas, AFP reports.
Washington also reiterated that Israel had every right to protect itself and to prevent sophisticated weaponry from getting into the hands of Hizbullah, following several airstrikes, allegedly carried out by Israel, on sites in Damascus.
"We are highly skeptical of suggestions that the opposition could have or did use chemical weapons," said White House spokesman Jay Carney.
"We find it highly likely that any chemical weapon use that has taken place in Syria was done by the Assad regime. And that remains our position," Carney said, according to AFP.
A senior U.S. official separately said that Washington had no information to suggest Syrian rebels had "capability or the intent to deploy or use such weapons."
Carla del Ponte, a former war crimes prosecutor, told Swiss public broadcaster RSI on Sunday that "according to the testimonies we have gathered, the rebels have used chemical weapons, making use of sarin gas."
The senior official also noted that "Ms. Del Ponte does not work on the same expert team, which the United Nations has assembled to go into Syria as they are two different parts of the United Nations organization."
The White House notified lawmakers in April that the United States had established, with "varying degrees of confidence," that a sarin gas attack had taken place in Syria.
Carney also reiterated President Barack Obama's statement at the weekend that Israel was within its rights to safeguard its security, though he would not directly comment on Israeli military reaction.
"Israel certainly has the right to be concerned about the transfer of sophisticated weapons to Hizbullah, and that has been a concern of Israel's for a long time," Carney said, according to AFP.
Carney also sidestepped a question about whether the slaughter of civilians in a civil war that has claimed more than 70,000 lives amounted to genocide.
"The terminology that may be used by courts or the United Nations or others, I will leave to them," he said.
"But it is heinous and despicable. It is the kind of action that long ago rendered Assad incapable of continuing in power with any kind of legitimacy," he added.
Obama is coming under increasing pressure in Washington from domestic political critics who are demanding action, including an operation to arm rebels or set up a no-fly zone to protect civilians.
The White House has said it is considering all its options, including reviewing its opposition to date to providing weapons to rebels, but Carney declined to provide a timeline for the deliberations.
Meanwhile on Monday, Sen. Robert Menendez, the Democratic chairman of the Senate Foreign Relations Committee, offered legislation that would allow the United States to provide lethal weapons to the Syrian opposition.
Menendez's bill would allow U.S.-provided arms, military training and supplies to go to groups that have been vetted and cleared, and establish a $250 million fund to help support a political transition in Syria.