Another question: If the Russians were the only ones to possess the Novichok poison, how could a country like Great Britain develop an antidote for it? On what would they test out the antidote?
Rumor is the Germans got a sample in the 90's.
Don't forget that when the Iron Curtain fell, there was a 2nd 'Freeing of the Serfs' and chemists that worked on programs like that headed West.