Typhoon fighter jets from the UK's Royal Air Force and German Air Force scrambled to intercept three Russian aircraft flying over the Gulf of Finland and the Baltic Sea.
The jets, which are part of NATO's Air Policing Unit in the Baltics, escorted and identified Russian fighters and intelligence aircraft on April 14.
One of the aircraft was a Russian Air Force IL-20 (NATO reporting name: Coot-A) intelligence aircraft transiting from mainland Russia to the Kaliningrad enclave.
It was met by two Russian SU-27 (NATO reporting name: Flanker-B) fighter jets based in Kaliningrad which escorted the IL-20 south through the northwest area of the Estonian flight information region.
The Coot-A is a signals intelligence variant of the IL-20 aircraft and was flying in a safe and professional manner, the RAF said in a statement published on Monday.
The RAF and German Typhoons escorted the Coot-A and Flanker-Bs through the Estonian flight information region before handing over to Saab Gripen fighters of the Swedish Air Force.
The RAF said it is common to see Russian military aircraft flying over the Baltic Sea and this was a "routine intercept".
The two forces are currently working together as part of Operation Azotize, to protect NATO's eastern flank. They are stationed at Estonia's Ämari Air Base.
Russian jets often fly close to Baltic airspace. Last year, NATO jets scrambled over 200 times to respond to incidents.
Less commonly, Russian aircraft also breach Estonian airspace. This has occurred 40 times since 2016.
Editor: Helen Wright