The Russian Foreign Ministry said in a statement that it is also ordering the closure of the British Council in Russia and ending an agreement to reopen the British consulate in St. Petersburg.
It ordered the diplomats to leave within a week.
The statement said the government could take further measures if Britain takes any more "unfriendly" moves toward Russia.
Russias's Foreign Ministry summoned the British ambassador to Russia on Saturday.
British Prime Minister Theresa May this week ordered 23 Russian diplomats expelled to punish Russia over the poisoning of Sergei Skripal and his daughter Yulia in the city of Salisbury.
British Ambassador Laurie Bristow is expected at the Russian Foreign Ministry late Saturday morning.
Britain's foreign secretary accused Russian President Vladimir Putin of personally ordering the poisoning of the Skripals, who remain hospitalized in critical condition after the March 4 attack. Putin's spokesman denounced the claim.
While Russia has vigorously denied involvement in the attack, Western powers see it as the latest sign of alleged Russian meddling abroad. The tensions threaten to overshadow Putin's expected re-election Sunday for another six-year presidential term.
Meanwhile new tensions have surfaced over the death this week of a London-based Russian businessman, Nikolai Glushkov. British police said Friday that he died from compression to the neck and opened a murder investigation.
Russia also suspects foul play in Glushkov's death and opened its own inquiry Friday.
British police said there is no apparent link between the attack on Glushkov and the poisoning of the Skripals, but both have raised alarm in the West at a time when Russia is increasingly assertive on the global stage and facing investigations over alleged interference in the Donald Trump's election as U.S. president.
The source of the nerve agent — which Britain says is Soviet-made Novichok — is unclear, as is the way it was administered. Russia has demanded that Britain share samples collected by investigators.
Top EU diplomats were expected to discuss next steps at a meeting Monday, with some calling for a boycott of the upcoming World Cup in Russia. British Prime Minister Theresa May is seeking a global coalition of countries to punish Moscow.
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