Bulgarian authorities have declared two Russian diplomats persona non grata and asked them to leave the country within 27 hours, said the Russian Embassy in Sofia.

-The Foreign Ministry of Bulgaria today summoned the adviser-envoy. He was handed a note declaring the embassy staff persona non grata. They must leave Bulgaria within 72 hours," the embassy was quoted as saying by the Russian state-run TASS news agency.

On Saturday, Bulgarian Prime Minister Boiko Borisov announced a plan to expel Russian diplomats over a spying scandal.

On Friday, Bulgaria's Attorney General said six current and former employees of the country's Defense Ministry and military intelligence were detained on suspicion of spying for Russia.

A district military court placed five of them in custody at the request of the prosecution on Monday. One suspect was released on bail as the prosecutor's office did not insist on his arrest.