Strasbourg: EU foreign affairs head Federica Mogherini told AFP on Wednesday that a high-stakes Ukraine peace summit in Minsk would be a turning point in the conflict.
Mogherini also urged Russia to take the chance to become a "responsible actor" and help end the 10-month war in the former Soviet state.
"It is something (that) is going to be a turning point for good or for bad... if tonight in Minsk we manage to reach an agreement," Mogherini said in an interview.
"If we do not, then all the options, all the developments that one can imagine for Ukraine itself, but also for Europe, for relations between Russia and the EU and the rest of the world, definitely, one can say (they would be) at the least, worrying."
Her comments came hours before the leaders of Ukraine, Russia, France and Germany were to hold peace talks in the Belarussian capital aimed at ending the crisis.