Russia declared 2 Bulgarian diplomats ‘persona non grata’ on Tuesday and ordered them to leave the country in response to Sofia’s expulsion of 2 Russian diplomats last month for suspected espionage.

The move followed Moscow’s decision to kick out diplomats from the Czech Republic, Poland and the United States in a flurry of expulsions over the past 5 days in retaliation for the barring of its own staff, which reflects a sharp deterioration in its relations with the West.

Kremlin spokesman Dmitry Peskov announced on Tuesday that Russia was not to blame for the growing tensions, saying foreign countries should refrain from “mass anti-Russia psychosis”.

In March, Bulgaria threw out the Russian diplomats after prosecutors charged 6 people, including current and former military intelligence officers, with spying for Moscow.

Russia’s foreign ministry identified 2 employees at the Bulgarian embassy in Moscow and said it had ordered them to leave Russian territory within 72 hours.

Bulgaria’s foreign ministry confirmed that its diplomats were declared ‘persona non grata’ and that the action was a direct response to its expulsion of Russian diplomats last month.

“No other reasons for the actions of the Russian authorities were pointed out at today’s meeting,” it said in a statement.