According to a statement posted on its official website, the Ukrainian Goverment has this afternoon announced that it is "suspending" the process of EU-Ukraine integration for "national security" reasons. Instead of committing to the EU deal, it proposes the creation of a trilateral commission between itself, Russia and the European Union.
Earlier in the day Ukraine's Parliament failed to pass laws to meet the conditions laid down by the EU, including the release of jailed former PM, Yulia Tymoshenko. The ruling Party of the Regions effectively refused to take part in the voting.
See:
The Economist: Playing East Against West
The Guardian: Ukraine suspends talks on EU trade pact as Putin wins tug of war
Wall Street Journal: Hopes For EU Deal With Ukraine Dim
Reuters: Ukraine drops plan to go West, turns East
BBC: Ukraine suspends preparations for EU trade agreement
Financial Times: Ukraine freezes trade talks with EU
Daily Telegraph: Ukraine halts preparations for EU trade deal
Guardian: Ukraine fails to pass bills freeing Yulia Tymoshenko before EU summit