The leaders of Ukraine, Russia, France and Germany plan to speak again Monday as deadlines are set to expire on both a cease-fire in eastern Ukraine and for Russia to avoid new sanctions by the European Union.
Ukrainian President Petro Poroshenko said Sunday after the leaders took part in a two-hour, four-way phone call that the cease-fire he declared June 20 would run through at least Monday night.
The EU is threatening more penalties against Russia if it does not use its influence on pro-Russian separatists in Ukraine.
French President Francois Hollande's office said the leaders told Russian President Vladimir Putin that they hoped "results are achieved by Monday."