Ukraine's prime minister is accusing Russia of carrying out a "military aggression" which has "no reason and no grounds" and is unacceptable.

Arseniy Yatsenyuk told the U.N. Security Council on Thursday he is convinced Russians don't want war.

He urged Russia's leaders to heed the people's wishes and return to dialogue with Ukraine.

"If we start real talks with Russia, I believe we can be real partners," Yatsenyuk said.

He said Ukraine gave up the world's third-largest nuclear arsenal in 1994 in exchange for guarantees of its independence and territorial integrity.

After Russia's recent actions, Yatsenyuk said, "it would be difficult to convince anyone on the globe not to have nuclear weapons."

Russian troops now control the Crimean Peninsula, where voters decide Sunday whether to become part of Russia.