Yea, I deny that. I would be more than willing to bet the “majority” of ISIS fighters from Europe are not from Russia. I bet there is ten times that number from Turkey alone, much less France.
Russian Nationals, Russia’s own government says they have 2,000 Russian Nationals fighting in ISIS. They acknowledge the number might be higher. http://www.iraqinews.com/arab-world-news/2000-russian-fighting-isis-syria-iraq/
So, England and France and Turkey may but I have not seen confirmation.
One of ISIS’s top commanders is “Omar the Chechen”, he’s from Georgia but a lot of Russian speakers are in ISIS.