The unidentified Russian diplomat was accused of committing espionage.
According to a Ukrainian foreign ministry spokesman: "The naval attache of the Russian Embassy in Ukraine has been declared persona non grata for acts incompatible with his diplomatic status, in accordance with the 1961 Vienna Convention on Diplomatic Relations."
Those "incompatible" acts included unspecified "spying activities on April 30th," according to the ministry's Facebook page.
The spokesman noted, "The diplomat will have to leave the territory of the country as soon as possible."
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