(CNN) -- Syria has begun detailing its chemical weapons arsenal, releasing an "initial declaration" of its stockpile, a spokesman for the U.N.-backed Organization for the Prohibition of Chemical Weapons said Friday.
More details about Syrian President Bashar al-Assad's chemical weapons program are expected within the next day or two, spokesman Michael Luhan said.
The international chemical weapons watchdog has been charged with overseeing the removal of al-Assad's chemical weapons arsenal from Syria, part of a U.S.-Russian plan aimed at averting American military airstrikes.
The information submitted by Syria is now being reviewed by the OPCW, he said.
The group's executive council -- which was to meet Sunday at The Hague, Netherlands -- has postponed the meeting until sometime next week, Luhan said, because "more time is needed" to review Syria's chemical weapons disclosure and agree to put in place a framework for the U.S.-Russia plan.
This jibes with a timeline in the U.S.-Russian deal forged last week in Geneva, Switzerland, to begin destroying Syria's chemical arsenal. Under the Geneva framework deal, al-Assad was given a week beginning last Saturday to declare the weapons program.
"This is irregular," Luhan said, explaining that this level of fast-tracking the disclosure of chemical weapons "has never been done before."
The normal 60-day process for declaring arms is being expedited to seven days "because of the extraordinary concern about Syria's weapons," he said.
"Until now, each country has been typical. The United States, Russia, Libya, India, none have been in a state of war or conflict," Luhan said.
Once the group has received Syria's full declaration, Luhan said, "we have to go through it in detail and plan how to conduct the on-the-ground inspection mission, to verify the accuracy of the declaration and put seals on all the materials to make sure they are secure."
A technical briefing on the Syria mission that was to have been held Monday will be rescheduled once a new date has been set for the executive council meeting.
Officials report Syria moving stockpiles
The Syrian regime is again moving around its stockpile of chemical weapons, leaving the United States trying to figure out what al-Assad will do next with his deadly arsenal, officials say.
CNN has learned that the U.S. intelligence community is closely watching the latest developments as diplomats try to form a plan for al-Assad to relinquish those stockpiles to international control.
One U.S. official with access to the latest intelligence on Syria tells CNN the regime "is actively moving its stockpiles in the last 24 hours."
The official, speaking on condition of anonymity, says the latest intelligence information shows there is movement at additional sites beyond what the United States had observed in the last two weeks.
"It's continuous but still unclear what they are really doing," the official said.
Officials don't know whether the weapons are being moved to account for the stockpiles to the United Nations or to hide them.
One official confirmed the Obama administration received specific information in recent months from Russia that the chemical weapons are secure. That assessment came from communications between Moscow and Damascus.
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.
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.
High-stakes diplomacy playing out
The stakes over halting the Syrian civil war heightened after an August 21 chemical weapons attack outside Damascus that the United States estimates killed about 1,400 people.
The United States and other Western nations blame al-Assad's forces for the attack. Russia and Syria say they think rebels used the weapons.
Citing international norms against the use of chemical weapons, President Barack Obama called for the authorization to use military force in Syria and wanted Congress to approve that move
As the United States threatened force to degrade al-Assad's ability to carry out more chemical weapons attacks, a diplomatic opportunity arose between Russia and the United States to put Syria's stockpile under international control.
U.S. Secretary of State John Kerry and Russian Foreign Minister Sergey Lavrov hammered out a deal in Geneva last week compelling Syria to accept the agreement.
Speaking ahead of next week's U.N. General Assembly meeting, Kerry said Thursday that while "the complete removal of Syria's chemical weapons is possible here, through peaceful means," urgency is needed.
The U.N. Security Council must be prepared to act next week, Kerry said, citing the U.N. chemical weapons report about the attack.
While the report did not blame any side for the attack, Kerry said that it offered "crucial details," making the case implicating al-Assad "only ... more compelling." Russia called the report "distorted" and said it was based on insufficient information.
Despite the diplomacy, the United States hasn't dropped its threat of force and is wary, saying Syria could be using the diplomacy as a stalling tactic.
"Time is short. Let's not spend time debating what we already know," Kerry said.
The United Nations estimates more than 100,000 people have died since March 2011, a period in which harsh government crackdowns against protesters devolved into an all-out civil war.
Another 2 million people have fled their homeland, and more than 4.25 million have been displaced within Syria, the United Nations says.