Nato has sent its F-35 fighter jets to intercept Russian planes. The operation on Thursday (May 27) is understood to have taken place after the Norwegian Air Force spotted the aircraft flying close to the border with Finland.
The planes were identified by Norway as a Mikoyan MiG-31 'Foxhound' and a Sukhoi Su-24 'Fencer' jet, MailOnline reports. The air force reportedly said the Russian planes flew to the Norwegian Sea before returning east.
Finland and Sweden have lodged applications to join Nato, heightening tensions with Russia which had warned the two countries against pursuing membership of the military alliance. In April Kremlin spokesman Dmitry Peskov said NATO was "not that kind of alliance which ensures peace and stability" and that Russia would "rebalance the situation" is Sweden and Finland joined.