War-weary Ukrainians are set to pick a pro-Western and nationalist-leaning parliament on Sunday that should give President Petro Poroshenko a mandate to end separatist conflict in the east, but may inject new tension into ties with Russia.It is the first parliamentary election in the ex-Soviet republic of 46 millions since street protests in the capital last winter forced Moscow-backed leader Viktor Yanukovich to flee and ushered in a pro-Europe leadership under Poroshenko.The results are expected to turn a political grouping supporting the 49-year-old confectionery tycoon into the leading force in the 450-seat assembly, giving him a mandate to pursue his peace plan for the east and carry out deep reforms sought by Ukraine's European Union partners.Poroshenko said on Saturday in a televised address he wanted a majority to emerge that would see through laws to support a pro-Europe agenda and break with the Soviet past."Without such a majority in parliament, the President's program ... will simply remain on paper," he said.With diminished pro-Russian influence and following a strong European integration agenda, it will be one of the most radical parliaments since Ukraine gained independence in 1991.The emergence of a strong presence committed to a united Ukraine will place a fresh strain on ties with Russia which the Kiev leadership blames for backing rebels in a conflict that has killed more than 3,700 people and destroyed the economy.