US Edition RAF Typhoons were scrambled to intercept two Russian long-range bombers off northern Scotland on Wednesday, in the latest in a series of provocative operations by the country's air force.
As tensions between Nato and Russia have worsened over the Ukraine crisis, Moscow has significantly increased the number of military flights probing Nato airspace - and submarine activity probing its waters.
The number of interceptions over the Baltic States trebled last year and Nato members including Britain have stepped up air policing support in the area.
Russia’s TU-95 Bear bombers - strategic bombers capable of carrying nuclear weapons - make probing flights towards UK airspace about once a month.
The Ministry of Defence says the Russian bombers have never violated Britain’s sovereign airspace, which extends 12 nautical miles from the coast, and publicly regards them as more of a routine nuisance than a threat.
But defence officials have expressed mounting concern over the nature of the flights. Michael Fallon, the then-defence secretary, said the appearance of Bear bombers over the Channel in February marked the first time they had been seen in that area “since the height of the Cold War.”
"We had to scramble jets very quickly to see them off,” he said.