"On September 3, Russian airspace control devices detected two air targets approaching the Russian state border over the neutral waters of the Barents Sea," the statement says.
To identify air targets and prevent violations of the Russian state border, a MiG-31 fighter from the Northern Fleet's air defence forces was scrambled, it said.
"The crew of the Russian fighter jet identified the air targets as US Air Force strategic reconnaissance aircraft RC-135 and Royal Air Force reconnaissance aircraft Sentinel R1," the statement says.
The entire flight of the Russian fighter MiG-31 was carried out in strict accordance with international rules for the use of airspace, the NDCC said. No violations of the Russian state border by US and UK aircraft were allowed, it said.