■ Russia expelled 23 British envoys in retaliation for the U.K.’s expulsion of Russians.

Both sides threaten more retaliatory measures in poisoning

MOSCOW — Russia announced Saturday it is expelling 23 British diplomats and threatened further retaliatory measures in a growing diplomatic dispute over a nerve agent attack on a former spy in Britain.

Britain’s government said the move was expected, and that it doesn’t change their conviction that Russia was behind the poisoning of ex-agent Sergei Skripal and his daughter in the English city of Salisbury. Prime Minister Theresa May said Britain will consider further retaliatory steps in the coming days alongside its allies.

The Russian Foreign Ministry ordered the 23 diplomats to leave within a week. It also said it is ordering the closure in Russia of the British Council, a government-backed organization for cultural and scientific cooperation, and is ending an agreement to reopen the British consulate in St. Petersburg.

The announcement followed Britain’s order this week for 23 Russian diplomats to leave the U.K. because Russia was not cooperating in the case of the Skripals, who were found March 4 poisoned by a nerve agent that British officials say was developed in Russia. They remain in critical condition and a policeman who visited their home is in serious condition.

Britain’s foreign secretary accused Russian President Vladimir Putin of personally ordering the poisoning of the Skripals. Putin’s spokesman denounced the claim.

Britain’s Foreign Office said Saturday that “Russia’s response doesn’t change the facts of the matter — the attempted assassination of two people on British soil, for which there is no alternative conclusion other than that the Russian State was culpable.”

The British Council said it was “profoundly disappointed” at its pending closure. The organization has been operating in Russia since the 1991 fall of the Soviet Union.