Ukraine says it has expelled two Hungarian diplomats hours after the country’s main security agency said that it had arrested two people on suspicion of spying for Hungary by gathering intelligence on Ukraine’s military in the west of the country.

Ukrainian security services claimed to have uncovered a Hungarian spy ring gathering information about military activities in Ukraine’s western Transcarpathia region.

Hungary's foreign ministry then responded to the allegations by expelling two Ukrainian diplomats, accusing them of engaging in Ukraine's own espionage activities. The incident marks the first time in Ukraine's history that a Hungarian espionage operation had been discovered,