Russia's Defence Ministry said on Tuesday that Britain has requested permission for its RC-135 spy plane to fly over Russia, a move it termed "a deliberate provocation".
There was no immediate response from Britain's Ministry of Defence to a Reuters request for comment.
A U.K. Ministry of Defence source denied that Britain had asked permission to fly a spy plane over Russia.
The Russian ministry said that Russia's airforce had been tasked with preventing any violations of Russian airspace.
