U.S. Defence Secretary Leon Panetta

REUTERS

Syrians have moved some of their chemical weapons capability to better secure it, but the country's main chemical weapons sites remain intact and secure under government control, U.S. Defence Secretary Leon Panetta said on Friday, citing U.S. intelligence.

Responding to questions about the security of Syria's chemical weapons sites, Panetta said U.S. intelligence showed the major Syrian sites were secure in government hands, but some chemicals had been moved, reports Reuters.

It was not clear when the movement took place, or even if it was recent, but Panetta told a Pentagon news conference it had occurred in more than one case.

"There has been some intelligence that with regards to some of these sites, that there has been some movement in order for the Syrians to better secure ... the chemicals," he said. "So while there's been some limited movement, again the major sites still remain in place, still remain secure."

U.S. officials believe Syria potentially has dozens of chemical and biological weapons sites scattered across the country. Its stockpiles are thought to include nerve agents such as VX, sarin and tabun.

An 18-month-old uprising against Syrian President Bashar al-Assad has killed 30,000 people and the violence is escalating sharply, say activists. World powers are divided over the crisis, which has descended into civil war.

While the United States has not intervened militarily in Syria, President Barack Obama has warned Assad that any attempt to deploy or use chemical or biological weapons would cross a "red line" that could provoke U.S. action.

"We have been very clear to the Assad regime, but also to other players on the ground, that a red line for us is (if) we start seeing a whole bunch of chemical weapons moving around or being utilized," Obama said in late August. "That would change my calculus."