RAF fighter jets were scrambled to intercept Russian aircraft to the west of Shetland.
The two Russian Tu-142 Bears - used as strategic bombers and long-range maritime patrol planes - were shadowed on Wednesday.
The air force scrambled two pairs of Typhoons from its Quick Reaction Alert programme at RAF Lossiemouth in Moray.
Air Chief Marshal Mike Wigston, chief of the air staff, said: "These Russian bombers do not comply with international air traffic rules, are a hazard to airliners and are not welcome in our airspace."
He said the reaction "ensured these Russian aircraft posed no hazard".
RAF Lossiemouth added: "At no point did the aircraft enter our sovereign airspace."
Last month, RAF jets were also scrambled from Lossiemouth after reports of unidentified aircraft flying towards UK airspace.