The UK, Sweden, France, Germany and The Netherlands are confident that Alexei Navalny was poisoned with a lethal toxin.
This is the conclusion of our Governments based on analyses of samples from Alexei Navalny. These analyses have conclusively confirmed the presence of epibatidine.
Epibatidine is a toxin found in poison dart frogs in South America. It is not found naturally in Russia.
Now what?
Do nothing. Be afraid of their own shadow, and do not provoke Russia, avoid conflict at any cost, do not help Ukraine (too much), and wait for the problem to solve itself. Call Putin a dozen of times, maybe.