Ukraine's interim prime minister alleged that Russia's occupation of Crimea poses a security threat to "the whole world."
Arseniy Yatsenyuk told a news conference in Kiev on Wednesday that the "Russian government has never had and never will have any grounds for the military aggression on the territory of Ukraine."
He added: "What's happening today on the territory of the Autonomous Republic of Crimea represents a threat not only to the security of Ukraine, but also to the whole world. And the responsibility for such actions lies only on Russia."
Russian President Vladimir Putin does not recognize Ukraine's new leaders. Kiev has accused Moscow of a military invasion in Crimea, a charge Putin denies.
The Associated Press contributed to this report.