The foreign ministers of Germany, Russia, Ukraine and France are scheduled to meet on January 12 for talks on the crisis in Ukraine.
The meeting in Berlin comes days ahead of a possible meeting of the same countries' leaders in the Kazakh capital, Astana over the conflict in Ukraine.
But German Chancellor Angela Merkel told Russian President Vladimir Putin on January 10 that it was too early for such a summit.
Merkel said that for the meeting to be successful there has to be progress on implementing a much-violated peace deal that was reached in Minsk in September.
French President Francois Hollande has said he would go to Astana only on condition there's a chance of making progress.
More than 4,700 people have been killed in fighting between government forces and pro-Russian separatists in eastern Ukraine since April.