Russia's FSB security service announced Friday that it had revoked the accreditation of six British diplomats in Moscow, accusing them of espionage and sabotage.
The British Embassy in Moscow had not yet responded to a Reuters request for comment.
The FSB, the main successor to the Soviet KGB, claimed to have documents showing that a British Foreign Office department overseeing Eastern Europe and Central Asia was involved in escalating political and military tensions and working to ensure Russia's strategic defeat in its war against Ukraine.
"Thus, the facts revealed give grounds to consider the activities of British diplomats sent to Moscow by the directorate as threatening the security of the Russian Federation," the FSB said in a statement.
"In this connection, based on documents provided by the Federal Security Service of Russia and in response to numerous unfriendly steps taken by London, the Ministry of Foreign Affairs of Russia, in cooperation with the relevant agencies, has terminated the accreditation of six members of the political department of the British Embassy in Moscow, whose actions showed signs of spying and sabotage," the statement continued.
The six diplomats were named on Russian state TV, which also showed photographs of them.
"The English did not heed our hints about the need to stop this practice of carrying out intelligence activities inside Russia, so we decided to expel these six to begin with," an FSB employee told the Rossiya-24 state TV channel.
The FSB said Russia would ask other British diplomats to leave if they were found to be engaged in similar activities.
Russian Foreign Ministry spokeswoman Maria Zakharova was cited by the state TASS news agency as saying that the British Embassy’s activities in Moscow had gone well beyond diplomatic norms and accused it of deliberately engaging in actions designed to harm the Russian people.