The FSB, the main successor to the Soviet-era KGB, named the British diplomat as Gareth Samuel Davies, a second secretary at the Moscow embassy, and said he was working undercover for Britain’s intelligence service.
Russian media carried pictures of the diplomat. Russia said he has been given two weeks to leave Russia.
Russia’s foreign ministry summoned Britain’s charge d’affaires in Russia, Danae Dholakia, to issue a formal protest about the situation.
Russia warning
”It was again stressed that Moscow would not tolerate the activities of undeclared British intelligence officers in Russia,” the foreign ministry said in a statement.
”A warning was also issued that if London escalates the situation, the Russian side will give a decisive ’mirror’ response,” it said.
Protesters at the foreign ministry chanted anti-British slogans in front of the British diplomatic car carrying the charge d’affaires.
Britain’s Foreign Office said it was not the first time such ”malicious and baseless accusations” had been made against British diplomats in Russia.
”Their targeting of British diplomats comes out of desperation and actions like this undermine the basic conditions required for diplomatic missions to operate,” it said. ”We are carefully considering our options in response.”
Amid the war in Ukraine, Russia and the West have repeatedly accused each other of unfurling espionage campaigns of an intensity not seen since the depths of the Cold War.
New cold war
Russia says that the Central Intelligence Agency (CIA), Britain’s Secret Intelligence Service, known as MI6, and France’s DGSE have all stepped up attempts to steal secrets, recruit Russians and sow discord inside Russia.
Western European spy chiefs say that the FSB, Russia’s SVR foreign intelligence service and the GRU military intelligence service have mounted major cyber attacks and sabotage campaigns across the Western world, something Moscow denies.
Russia's enemy number one is Britain
As the US under Donald Trump seeks to reset ties with Moscow and broker peace between Russia and Ukraine, Britain has been granted the status of Russia’s public enemy number one.
On Russian state television, ”Perfidious Albion” is cast as a scheming global intelligence power that is meddling behind the scenes from Washington to Iran in a duplicitous bid to undermine Russian interests across the world.
Russia has imposed Soviet-style restrictions on British diplomats requiring them to give notice of any plans to travel beyond a 120-km (75-mile) radius.
Diplomatic postings to Moscow are now considered among the most difficult in the world by Western countries. The US State Department ranks Moscow alongside Freetown, Mogadishu, Damascus and Kabul in hardship terms.
Western diplomats in Moscow say intrusive surveillance and harassment are frequent. Russia has long complained that its own diplomats are routinely harassed in major Western capitals.
With inputs from agencies
