"We have the information that provocations using chemical substances are constantly being prepared by militants and terrorists. Our US colleagues and their allies remain unresponsive to this information. In the OPCW [the Organization for the Prohibition of Chemical Weapons], a so-called attributive mechanism has been created in violation of the Chemical Weapons Convention, which now has to act, apparently, taking into account the principles that are politically formulated by Western countries in this field. We advocate the investigation of all cases with the use of poisonous weapons, but this must be an investigation and not just the pinning of labels," Ryabkov told reporters.
He noted that the investigation should entail visits to the scene of the incident, interviews with witnesses and collection of uncontaminated evidence.
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Previous such incidents only resulted in accusations against Damascus and no probes of this kind, the diplomat stressed.
"As a result, trust in the OPCW, once the most effective, successful international organization, which is universal in this area, has been undermined", Ryabkov added.
The Russian Defence Ministry said earlier in May that militants of al-Nusra Front terror group were preparing to stage a false-flag provocation in Syria's Idlib province to frame the Russian Aerospace Forces and the Syrian army for allegedly attacking civilians with chemical weapons.
Last year, the United States, United Kingdom and France used claims of chemical attacks in Syria's Khan Sheikhoun, Duma and Eastern Ghouta to justify missile strikes on Syria, without waiting for the results of an independent investigation. The Syrian government has denied any role in the attacks.
* al-Nusra Front [the Nusra Front, Jabhat al-Nusra] — a terrorist group banned in Russia and a number of other countries