Earlier in the day, the OPCW said that its fact-finding mission had established the use of sarin in the April 4 incident in Idlib.
"I think that these are attempts to topple the Syrian authorities, to demonize President [Bashar] Assad. We have witnessed this policy in several periods of time and it is yet another example of such policy. Actually, our partners do not need the results of the investigation," Shulgin told the RT broadcaster.
The official added that the western partners of Russia had been "sure that the Syrian authorities were engaged in the incident" since April.
Reacting to the incident, Washington, which had not presented any proof of chemical weapon use by Damascus, launched 59 cruise missiles at the Syrian governmental military airfield in Ash Sha’irat on April 7.
On April 21, Assad told Sputnik that there was no chemical weapon attack in Idlib, adding that the reports of it were a false flag and fabrication which was supposed to justify a US missile strike on the Syrian airbase.