File photo of Syrian President al-Assad in Damascus.
File photo showing Syrian President al-Assad in Damascus. Reuters

Closely following earlier reports that Syria had started moving some parts of its huge stockpile of chemical weapons out of the storage, the most senior Syrian official to defect to the opposition has said that the Syrian regime will not hesitate to use chemical weapons in a last-ditch effort at survival.

Nawaf Fares, former Syrian ambassador to Iraq, told the BBC that unconfirmed reports indicated chemical weapons might have already been in use in quashing the 16-month old uprising.

He added that the regime, in collaboration with al-Qaeda, devised the bombings across Syria.

There is information, unconfirmed information of course, that chemical weapons have been used partially in the city of Homs, Fares said Tuesday when asked about the likelihood of Syrian President Bashar al-Assad using chemical weapons against the rebels.

U.S. officials reported Friday that the Syrian government had started moving parts of its chemical weapons supply, but were uncertain whether the move was a precautionary measure against safeguarding the stock from falling into the hands of the opposition, or whether it was for something that can assure a catastrophe in the region.

Syria is believed to own one of the largest undeclared stockpiles of chemical and biological weapons in the world, including the sarin nerve agent, mustard gas and cyanide, the U.S. officials said, as reported by the New York Times.

Representative Mike Rogers (R) who is the Chairman of the House Intelligence Committee expressed alarm over the weapons of mass destruction (WMD) in Syria.

I have made clear for some time now that I am gravely concerned about the large stockpiles of advanced weapons in Syria, Rogers said in a statement Friday.

These dangerous weapons, that include advanced shoulder-fired anti-aircraft and anti-tank missiles, and biological and chemical weapons, make Libya look like an antique gun show. Several dangerous terrorist groups, including al-Qaeda in Iraq, are active in Syria, and I am very concerned that as the situation in Syria deteriorates, these weapons could fall into the wrong hands, he said.

We cannot discount that the Assad regime could make a decision to use these weapons in an act of desperation, and we must act accordingly, he added.

Obama administration Friday warned the regime to keep its chemical and biological arsenal secure.

We have repeatedly made it clear that the Syrian government has a responsibility to safeguard its stockpiles of chemical weapons, and that the international community will hold accountable any Syrian officials who fail to meet that obligation, a State Department spokeswoman Victoria Nuland said.

The Defense Department spokesman George Little said: We would caution them strongly against any intention to use those weapons. That would cross a serious red line.

Signaling the growing concern within the U.S. Congress over the Syrian WMD, senators McCain, Graham and Lieberman issued a joint statement expressing alarm.

If Assad is transferring chemical weapons from secure sites to the battlefield, it significantly raises the risks that they will be used or that control over these weapons could be compromised. These are unacceptable risks for the United States and the entire international community, and they would threaten our vital national security interests, the statement said.

If that is the case, the Administration should convene an urgent session of the UN Security Council to consider a Chapter 7 resolution demanding that Assad relinquish his weapons of mass destruction to responsible international control - and authorizing the use of all necessary means to enforce this demand. If Russia and China stand in the way, the United States must rally our friends and allies to act, they said.

This isn't the first time that the Syrian government has come under international scrutiny for the use of WMD.

The first and so far the only officially reported Syrian employment of chemical weapons was in 1982, during a conflict between the rebels of the Muslim Brotherhood and the ruling Alawite sect.

In February 1982, the Muslim Brotherhood clashed with the government forces under President Hafez al-Assad, in the city of Hama. Over two weeks of violence resulted in the deaths of 7,000 to 35,000 people, including an estimated 1,000 soldiers.

Lethal cyanide gas was reportedly used by the Syrian regime in the slaughter of Sunni residents of Hama. Use of hydrogen cyanide was unsubstantiated, but reports in the 1980s suggested that hydrogen cyanide was used by the Syrian government against the insurgents.