Germany says it won't recognize Russia's annexation of Crimean Peninsula, one year after a referendum that Ukraine said was illegitimate.
The issue of Crimea's status has taken a back seat in recent efforts to broker a peace deal for eastern Ukraine, where government forces are battling separatists backed by Russia.
German Chancellor Angela Merkel has been a key figure in those talks.
Government spokesman Steffen Seibert says Germany supports Ukraine "within its internationally recognized border" and accused Moscow of threatening peace in Europe.