Yanukovych wanted his cake and eat it too, no one agreed with a trilateral agreement.,neither russia or eu and it wasnt even on the table as an offer from either side so when it came to a descision he went against the Ukranian popular choice:-) the eu association agreement and instead went for the closer ties with russia, which by the way was to be a member of the eurasia group.Also important point was that ukraine had already signed an agreement with Eu and it was the refusal of yanukovych in signing the ratification into law that caused the uprising.