What don't we know about the Novichok attack?

Perhaps it's time for Theresa May to tell all of us what she told the EU the other day. The intelligence titbits she revealed to the EU convinced all of them to support the UK in its fight with Russia over the poisoning of Sergei Skripal and his daughter, Yulia. For those not on the need-to-know list - ie the general public - we are pretty sure Russia was behind the nerve agent poisoning for the following reasons: Novichok, the nerve agent, is a military substance only ever made in Russian laboratories as far as we know; the Russian KGB/FSB have done this before, they have a whole department that creates the nastiest poisons for operational use against people their president has on a hit list (the hit list is an educated presumption on my part); the Alexander Litvinenko case wasn't the first poisonining on British soil linked to Moscow, but the similarities with the Salisbury attack are stark and believable; Putin has publically threatened with a grim end anyone who betrays the Motherland. All these ingredients add up to a very convincing case. But Mrs May knows more than this. MI6 and/or MI5 have come up with some tasty intel which has made her even more sure than us lot that Moscow/Putin is guilty. After Moscow's totally outrageous expulsion of another 50 British diplomats, on top of the 23 already told to leave, it's time for the UK prime minister to reveal at least part of the secret intelligence which she acquired from her spymasters. Is there something so devastating - like definite proof of Putin's signature on the plot - that she has absolutely no doubt whatsoever that Moscow is to blame for the Salisbury poisoning? If so, why is she still trolling out the same phrase about it being most likely that Russia is guilty. A court of law would never convict on the phrase "most likely" or "probably". The circumstantial evidence is overwhelming but is that enough to get a conviction? Well, of course, we don't yet have any individuals under suspicion - apart from Putin - so the court of law scenario does not yet apply. But a dramatic piece of intelligence disclosed in a statement from the PM in the House of Commons would help the public to get to grips with this appalling incident and might turn the screws on Moscow. It's a risk. It's always tricky to reveal secret intelligence in case it points the finger at sources. But there will come a time when we will need to be told. At present it looks like a long long police investigation ahead of us and a never-ending diplomatic war. At least Yulia is getting better but I am assuming she knows nothing about the circmstances that led to her falling unconscious on a park bench next to her father.