"Chemical weapons with chlorine are still being used there [in Syria]," the US secretary of state said, calling it a violation of the all documents signed by Russia. "Russia bears responsibility for resolving this issue," Tillerson stated at a briefing following a meeting with Polish Prime Minister Mateusz Moravetski.
Moscow has already answered repeated accusations of covering up chemical weapons use in Syria, voiced at on the January 23 Paris meeting of the so-called International Partnership Against Impunity for the Use of Chemical Weapons, comprising 24 countries, except Russia and China, which weren't invited.
The attendees of the event accused Damascus of being responsible for chemical attacks in Syria and Russia of trying to cover up the alleged crimes of Syrian government troops. Moscow has repeatedly refuted these claims, calling them an endeavor to discredit the Syrian government led by Bashar Assad.
Commenting on the Paris meeting, Russian Deputy Foreign Minister Sergey Ryabkov called it a de facto attempt to substitute the functions of the Chemical Weapons Convention (CWC) and the UN Security Council, posing a real threat to the existing international non-proliferation regime.
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The diplomat countered the US accusations, saying that Washington remained the owner of the world's largest stockpile of chemical weapons, consisting of over 2,500 metric tons of the most dangerous weaponized toxic agents. Thus, the US side, as Ryabkov specified, preserved "the type of weapons of mass destruction that is forbidden to anyone else," saying Washington needed them "for some purpose."
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The allegationss were made amid the disputes around the report presented by the Organization for the Prohibition of Chemical Weapons (OPCW) and by the OPCW-United Nations Joint Investigative Mechanism (JIM). The analysis calls Syrian President Bashar Assad is responsible for the use of sarin in the Khan Sheikhoun incident, while the Daesh terrorist organization is responsible for the use of sulfur mustard in Umm Hawsh.
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The Russian Permanent Mission to the United Nations stated that the report was based mostly on assumptions and the selective use of facts.
In the meantime Damascus has repeatedly refuted any allegations of chemical weapons possession, the full destruction of which was confirmed by the OPCW. The Russian side, for its part, has called for an unbiased investigation into the reported chemical attacks not only in Syria, but everywhere in the world, pointing to the absence of tangible results in the work of the OPCW-UN mission on numerous occasions.
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In November, Russia vetoed a US-drafted resolution that aimed to prolong the mandate of the OPCW-UN JIM and submitted its own resolution. Russia's draft, co-sponsored by China and Bolivia, did not secure the required number of votes.