RAF fighter jets intercepted Russian military aircraft in the North Sea near UK airspace, the air force said.
It marks the third time in six days the Typhoons have been scrambled in response to Russian planes.
The planes were identified as two Russian Tu-142 Bear F anti-submarine warfare and maritime patrol aircraft.
The Quick Reaction Alert Typhoons, flown by pilots from RAF Lossiemouth in Moray, were launched from Leuchars Station in Fife where the pilots are temporarily based.
The RAF said the Typhoon pilots monitored the planes “while in our area of interest to ensure the flight safety of all airspace users operating in this busy portion of international airspace”.
“At no time did the Russian aircraft enter UK sovereign airspace,” the force added.
Air-to-air refuelling was provided by an RAF Voyager from RAF Brize Norton in Oxfordshire and a Nato E-3A sentry airborne early warning aircraft also assisted.
Nato allies, including France, Denmark and Norway, also launched their Quick Reaction Alert aircraft to assist in monitoring the Russian Tu-142s.
Air Officer Commanding 11 Group, Air Vice-Marshal Ian Duguid, said: “For the third time inside a week, the RAF has scrambled to defend the interests of the UK and Nato.
“It’s a sign of our continued resolve to work effectively with our Nato partners at all times and demonstrates the efficiency and resilience of our personnel, aircraft and systems.”
On Monday, Typhoons were scrambled from Leuchars as two Russian Tu-160 Blackjacks “operated within Nato’s area of interest”, according to the RAF.
Two days earlier, the fighter jets were sent out in response to two Russian Tu-142 Bear Fs operating near UK airspace.