International inspectors have found traces of sarin and VX nerve agent at a military research site in Syria that had not been declared to the global chemical weapons watchdog, diplomatic sources told the Reuters news agency on Friday.
Samples taken by experts from the Organization for the Prohibition and Chemical Weapons (OPCW) in December and January tested positive for chemical precursors needed to make the toxic agents, the sources told Reuters on condition of anonymity.
"This is a pretty strong indication they have been lying about what they did with sarin," one diplomatic source said. "They have so far been unable to give a satisfactory explanation about this finding."
In 2013, the United States threatened military intervention against Syria's government after sarin gas attacks that year killed hundreds of residents in Ghouta, a rebel-controlled suburb of the Syrian capital Damascus.
The Damascus government forestalled foreign intervention by agreeing to a U.S.- and Russian-brokered deal under which it joined the OPCW, admitting to having a chemicals weapons program and promising to eliminate it.
A joint mission between the UN and the OPCW was then tasked with eliminating Syria's chemical weapons program, and the government of President Bashar Al-Assad last year handed over 1,300 tons of chemical arms.
Damascus has denied using sarin or any chemical weapons in battle during Syria's continuing civil war.
The diplomatic sources told Reuters the sarin and VX nerve samples were taken from the Scientific Studies and Research Center, a government agency where Western intelligence agencies say Syria developed biological and chemical weapons.
Asked about the diplomats' account, OPCW spokesman Peter Sawczak replied, "Obviously we are working to clarify Syria's declaration. I cannot discuss any details of that process, but in due course the assessment team will issue a report."
An OPCW fact-finding mission has been investigating allegations of dozens of recent chlorine gas attacks in Syrian villages but is being refused access to the sites by the Assad government, the diplomatic sources said.
The finding of VX and sarin supports assertions by Western governments that Assad withheld some of his stockpile, or did not disclose the full extent of Syria's chemical capability or arsenal to the OPCW, according to diplomats and analysts.
OPCW inspectors have been to Syria eight times to verify the accuracy of the details of the chemical weapons program provided in an initial report, but keep returning with more questions than answers, the diplomats told Reuters.
Under the deal with Washington and Moscow, Syria agreed to permanently and completely destroy its chemical weapons program and cannot use poison gas in warfare.
The OPCW, which is not mandated to assign blame, said chlorine has been used "systematically and repeatedly" as a weapon in Syria after Damascus handed over its declared toxic stockpile.
The diplomats’ comments come one day after Syrian activists and a doctor reported new suspected chlorine attacks in the northwestern province of Idlib.
(Arutz Sheva’s North American desk is keeping you updated until the start of Shabbat in New York. The time posted automatically on all Arutz Sheva articles, however, is Israeli time.)