A British man suspected of spying for Russia in exchange for cash has been arrested in Germany, federal prosecutors said Wednesday.

       The suspect identified only as David S worked as local staff at the British embassy in Berlin until the time of his arrest.

       The federal prosecutor's office said in a statement: "On at least one occasion passed on documents he acquired as part of his professional activities to a representative of Russian intelligence.

       "The accused received a cash payment in an unspecified amount in return."

       Scotland Yard's counter-terror unit was also involved in the arrest, and the Met Police said the 57-year-old was detained as part of a joint operation.

       In a statement, the force said: "A 57-year old British national was arrested by German authorities on Tuesday, 10 August, as part of a joint investigation between the Met's Counter Terrorism Command and German counterparts.

       "The man was arrested in the Berlin area on suspicion of committing offences relating to being engaged in ‘Intelligence Agent activity’ (under German law).

       "Primacy for the investigation remains with German authorities. Officers from the Counter Terrorism Command continue to liaise with German counterparts as the investigation continues."

       The Met's Counter Terrorism Command is responsible for investigating alleged breaches of the Official Secrets Act.

       It said David S, who was taken into custody Tuesday in the eastern city of Potsdam on an arrest warrant issued on Aug 4, was believed to have been spying since November 2020 "at the latest".

       He is to appear later Wednesday before an investigating judge who will decide whether he will be remanded in custody.

       Germany has arrested a number of people in recent years accused of spying for Russia, but the capture of a suspect from a close ally is highly unusual.

       In June, German police arrested a Russian scientist working at a German university accused of working for Russian secret service since early October 2020 at the latest.

       He is also suspected of accepting cash in exchange for his services.

       Moscow is at loggerheads with a number of Western capitals after a Russian troop build-up on Ukraine's borders and a series of espionage scandals that have resulted in diplomatic expulsions.

       In June, Italy said it had created a national cybersecurity agency following warnings by Prime Minister Mario Draghi that Europe needs to protect itself from Russian "interference".

       The move came after an Italian navy captain was caught red-handed by police selling confidential military documents from his computer to a Russian embassy official.

       The leaders of nine eastern European nations in May condemned what they termed Russian "aggressive acts", citing operations in Ukraine and "sabotage" allegedly targeted at the Czech Republic.

       Several central and eastern European countries expelled Russian diplomats in solidarity with Prague, but Russia has branded accusations of its involvement as "absurd" and responded with tit-for-tat expulsions.

       The latest espionage case also comes at a time of highly strained relations between Russia and Germany on a number of fronts, including the ongoing detention of Kremlin critic Alexei Navalny, who received treatment in Berlin after a near-fatal poisoning.