This is where the critical nature of the EU comes in to play. Here we have the Ukraine being told they possibly will be part of NATO which potentially sets off a series of Events as I can not see Putin standing by - it is an extremely provocative move it it happens. Very pointed.
However, the EU will come into play here. For years they have tried to form an EU Army and have been thwarted by the UK constantly in the voting - essentially the UK is the USA lap dog ensuring reliance on NATO members from EU.
The EU without the UK will very likely form an EU army, and invitations will be sent to many countries including the Ukraine. They offer not only the benefit of EU Membership and the ECB, but also soon - protection. Until now you could never join the EU and not in some way be obligated to the USA through NATO, and with this unreasonable condition removed, it will become an attractive move for many countries seeking economic benefit as well as military might. Russia could and would accept an EU army as a preference to NATO as it means his energy supplies to the EU are assured and they can play more statesmanship with regards to dividing up Eastern Europe. Having EU members as part of NATO is always a thorny issue for Putin, but an EU Army is more tolerable with US interests abandoned, it would likely lead to more peace although the Middle East could become a hotbed with a new alignment of NATO.
If the Ukraine were to be accepted into NATO, there is real potential there for the first serious proxy war of the USA versus Russia in the proxy of Eastern Central Ukraine.
Fascinating. A very aggressive, very pointed threat to Russia.