I dont think Russia will take the bait. English (Refuse to call it UK Government, its not.) Government tried framing and antagonising them with the Skripal case, fucked that up. America tried antagonising them ith sanctions, failed. Then TrumpyDump backed himself into a corner with his relentless Tweeting (Seriously, the guy tweets more bullshit than a 14 year old girl) and had to bomb somewhere in Syria, so he picked some empty "chemical labs". Still, no military response from Russia.

Russia (Putin) is not stupid. He's also not weak.
Trump and Theresa May (Trumpatron and MayBot) are both.

If WW3 breaks out, you can guarantee Russia wont be the ones responsible. They have nothing to gain from it.