Scores of foreign ambassadors receive notices to leave the country, in a move that comes as retaliation for the coordinated expulsion of over 150 Russian diplomats by the UK and its allies.
Russia expelled diplomats from 23 countries on Friday in retaliation against the West in a spy row, in the biggest wave of tit-for-tat expulsions in recent memory.
The Russian foreign ministry said it had summoned the heads of missions from 23 countries — almost all of them European Union member states — to tell them that some of their diplomats had to leave.
The diplomats from France, Canada, Germany, Australia and other countries were earlier seen arriving at the Russian foreign ministry in flagged official cars.
Germany and Poland each said Russia was expelling four of their diplomats. Among the other countries that had similarly been told to pull their envoys were the Netherlands, Sweden, the Czech Republic, Finland and Lithuania.
Thirteen Ukrainian diplomats will also leave Russia.
The moves came in retaliation for the coordinated expulsion of over 150 Russian diplomats by Britain and its allies over a nerve agent attack against former double agent Sergei Skripal and his daughter Yulia in the English city of Salisbury on March 4.
The massive expulsion of diplomats on both sides has reached a scale unseen even at the height of the Cold War.
"This is certainly not a surprise," Dutch Foreign Minister Stef Blok said through a spokeswoman, referring to Moscow's expulsion of two of the country's diplomats.
Blok called upon Russia to cooperate with the ongoing investigation into the attack by the Organisation for the Prohibition of Chemical Weapons.
The Russian foreign ministry also gave Britain a month to cut the number of diplomatic staff in Russia to the same number Russia has in Britain.
In Britain, the government called the latest developments "regrettable" but remained adamant that Russia was in the wrong.
Russia also said it reserved the right to respond to the recent expulsion of Russian diplomats by Belgium, Hungary, Georgia and Montenegro.
In the Kremlin, President Vladimir Putin presided over a meeting of the country's Security Council which discussed the most recent retaliatory steps against Britain and its allies.
The Kremlin insisted it was not Russia that had started the diplomatic war with the West.
"Russia did not unleash any diplomatic war," Putin's spokesman Dmitry Peskov said. "Russia never initiated any exchange of sanctions."
On Thursday, Moscow had announced that it would expel 60 US diplomats and close the US consulate in Saint Petersburg after the expulsion of its own diplomats and the closure of one of its US consulates.
In all, more than 150 Russian diplomats have been ordered out of the US, EU members, NATO countries and other nations which are accusing Russia of being involved in the Skripal poisoning.
Foreign Minister Sergey Lavrov has said Moscow would respond with "tit-for-tat" measures, but they might "not only" be symmetrical.
US trying to recruit Russian diplomats?
Russia's Foreign Ministry on Friday accused US intelligence services of trying to recruit Russian diplomats expelled by the US.
The ministry said it saw a "sharp increase in provocative actions against Russian diplomats."
It said American intelligence services have engaged in "frantic efforts" to make cooperation offers to the expelled diplomats. The ministry described the alleged US overtures as "cynical and disgusting," adding that they have failed.
Skripal and his daughter 'improving rapidly'
The hospital where Skripal and his daughter are being treated said on Thursday that Yulia, 33, was "improving rapidly and is no longer in a critical condition," while 66-year-old Sergei remained in critical but stable condition.
Britain has said it is "highly likely" that Russia was responsible for the attack using the Novichok nerve agent developed in the Soviet Union, but Russia has angrily denied any involvement.