It's a quote from a leading Russian general, similar to the one made by another Russian general warning of a staged chemical weapon attack back in March,
a month before just such an attack was staged when Assad and Russia began liberating Douma.
It comes a few days after McCain's crazed neocon buddy:
John Bolton declared that the US would respond very strongly if Assad uses chemical weapons
again (Ha!) while attempting to liberate Idlib from the (Western-backed) Wahhabist terrorists currently controlling the place.
Your willingness to instantly declare it propaganda demonstrates the effects of the brainwashing inherent in the Western establishment mouthpieces masquerading as news outlets that you clearly regularly consume.