The situation is completely out of the hands of the EU, US and even the 'leader' of the opposition, Klitschko. Right now, it's the more radical side of the protesters which has grown tired of the continued negotiations which have gone nowhere, and after Yanukovich tried breaking the protest up yesterday, they've had enough and are on the offensive.
Unfortunately I think that the next thing we will see will be BTRs and BMPs rolling in.
EDIT: Scrap that, the BTRs are already there:
Live twitter updates -
https://twitter.com/BBCWorld/lists/bbc-kiev-feb-2014