Pro-Europe parties led by a group backing President Petro Poroshenko swept a parliamentary election in Ukraine on Sunday, an exit poll showed, giving him a mandate to end a separatist conflict and pursue democratic reforms. The survey, issued after voting stations closed in the ex- Soviet republic, gave Poroshenko's bloc 23 percent of the votes cast for the 29 competing parties, ahead of the party of his ally, Prime Minister Arseny Yatseniuk, on 21.3 percent.