Ukraine's prime minister is calling for continued Western unity in pressing Russia to fully implement a much-violated peace deal.

Arseniy Yatsenyuk said Thursday that Russia is "desperately trying" to split European Union countries, "but they're going to fail."

Yatsenyuk is in Berlin to meet Chancellor Angela Merkel, who has been a key figure in trying to broker a diplomatic solution to the crisis in eastern Ukraine.

He said during an appearance at the German Council on Foreign Relations think-tank that the Minsk cease-fire agreement dating back to September is still viable and the most urgent priority is to seal the Russia-Ukraine border.

Yatsenyuk says that everyone including Russia must "execute all 12 points of this Minsk deal."