By Barbara Starr

The Syrian regime is again moving around its stockpile of chemical weapons, leaving the United States trying to figure out what Bashar al-Assad will do next with his deadly arsenal.

CNN has learned that the U.S. intelligence community is closely watching the latest development as diplomatic efforts continue around forging a plan for al-Assad to relinquish those stockpiles to international control.

Obama administration officials at two agencies said the movement took place in recent days – since United States and Russia agreed on September 14 to a timetable for Syria to declare its chemical weapons inventory and then give them up.

“There is activity at known chemical weapons storage sites,” one official said. “What is unclear is whether they are moving them to consolidate the stockpile and then declare it, or are they moving it around to conceal it” in advance of reporting it to international inspectors.

U.S. satellites have observed truck convoys moving in and out of storage sites, but the ongoing intelligence challenge involves knowing where the trucks are headed and exactly what they are carrying, that official added.

“Call us skeptical” of Syrian intentions, the other official said.

Both asked to remain anonymous due to the sensitive nature of the information.

While Syria previously moved chemical stockpiles around apparently to avoid the risk of them falling into the hands of rebels, this time the motivation is not clear.

One official confirmed the Obama administration has received specific information in recent months from Russia that the chemical weapons are secure. That assessment came from communications between Moscow and Damascus.

But the U.S. intelligence community also has continued to use satellite imagery, intercepts and human sources on the ground inside Syria to develop its own picture.

At this point, the United States has no reason to believe the weapons are not secure. But as CNN previously reported, there is also disagreement within the intelligence community about whether the United States knows the location of the entire stockpile.