Moscow announced Monday it was expelling an Italian diplomat in response to the "unfriendly" removal of two Russian officials from Italy in March over spying allegations.
The foreign ministry said it had summoned Italy's ambassador and that he was informed Russia was "declaring 'persona-non-grata'" Rome's naval attache in Moscow, who would have 24 hours to leave the country.
Italy condemned Russia's decision to expel one of its diplomats as "unfounded and unjust".
The foreign ministry expressed its "deep regret" at the decision to expel the deputy naval attache of the Italian embassy in Moscow with 24 hours notice, saying: "We consider the decision unfounded and unjust because it is in retaliation for a legitimate measure taking by the Italian authorities in defence of their own security."
The story is being updated.
