Ukraine's SBU security agency said on Friday it had uncovered a spy network run by the Hungarian state to obtain intelligence about its defences, with Hungary responding to what it called "propaganda" by expelling two people at the Ukrainian embassy in Budapest.

Ukraine said Friday it had exposed a network of Hungarian spies trying to obtain defense secrets in a border region of Ukraine – the first time it said such an operation has been discovered.

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,