Russia has kicked out a British diplomat that Moscow has accused of spying.
The diplomat had his accreditation revoked and was told to leave the country in two weeks.
The FSB, Russia's security service, claimed the British diplomat "provided false information about himself".
Moscow also accused him of attempting to gather information about the Russian economy during informal meetings.
The FSB, the main successor to the Soviet-era KGB, said it had detected an "undeclared intelligence presence".
It added the diplomat was "carrying out intelligence and subversive activities that threaten the security of the Russian Federation", according to Russian media reports.
In a statement, the Russian Ministry of Affairs said Danae Dholakia, the British Chargé d'Affaires in Russia, was summoned over the claims that a diplomat had "knowingly provided false information about himself when applying for entry into our country".
The statement read: "Russian authorities also received information indicating that this employee belonged to the British intelligence services and identified evidence of his involvement in subversive intelligence work in our country."
It continued: "The British side was informed that previously uncovered instances of some British diplomats deliberately providing false information about themselves had already prompted our harsh response.
"They were also urged to convey to London a strong recommendation that British citizens, especially embassy staff, provide only accurate information about their past when applying for visas.
"It was particularly emphasized that Moscow will not tolerate the activities of undeclared British intelligence officers in Russia, and our uncompromising position on this issue will continue to be formulated in accordance with national security interests.
"Furthermore, a warning was issued that if London escalates the situation, the Russian side will immediately respond accordingly."
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Russian state media published a photograph of the diplomat accused of attempting to obtain information.
"In order to avoid negative consequences, including criminal liability, the FSB of Russia recommends that compatriots refrain from holding meetings with British diplomats," the FSB said.
Britain did not immediately respond to a request for a response, but when a British diplomat was expelled in January for spying, London branded the claims "baseless accusations".
On Russian state television, Britain is cast as "Perfidious Albion", a scheming global power meddling behind the scenes to undermine Russian interests.
Western diplomats in Moscow say intrusive surveillance and harassment are frequent, and a guide known as "Moscow Rules", developed by Western spies in the Soviet era to guard against complacency, has been updated for modern Russia.
Russia has imposed Soviet-style restrictions on most British diplomats, requiring them to give notice of places to travel beyond a 75-mile radius.
Earlier this month, Russia's ambassador to Britain denied that poison from a dart frog was used to kill opposition leader Alexei Navalny.
Andrey Kelin told Sunday Morning with Trevor Phillips that the death had "nothing to do with us".
Mr Navalny, 47, was killed while imprisoned in a Russian penal colony in 2024.
(c) Sky News 2026: Russia kicks out British diplomat Moscow accused of spying

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