RAF combat aircraft have been scrambled after reports Russian bombers were heading towards UK airspace.
The Typhoon jets were dispatched from RAF Coningsby in Lincolnshire on Wednesday afternoon following the security alert.
An RAF spokesman said the situation was "on-going" and was not uncommon.
He said: "We have Typhoons up on a quick reaction alert. The situation is on-going."
It is believed the aircraft are with the Long Range Aviation branch of the Russian military. They have never penetrated UK airspace.
Typhoon jets can be deployed in a range of operations, including combat.
More recently, Typhoons have been involved in the campaign against Islamic State in Syria, with jets dispatched from the British military base of RAF Akrotiri.