Nato has kicked off its largest military exercises since the Cold War across northern Europe as the West tries to keep up with Russia's growing military presence in the Arctic and the Baltic Sea.

Some 50,000 soldiers, 250 aircraft, 65 ships and 10,000 tanks and other ground vehicles are taking part in the Trident Juncture war games that began Thursday at locations from Iceland to Finland.

With 31 countries involved, they are meant to test Nato's response to an attack on Norway, where most of the drills are taking place.

Footage showed treaded vehicles barrelling down muddy forest tracks, soldiers marching through barren northern landscapes and F-18 Super Hornet fighter jets taking off from remote runways.

While the envisioned aggressor state has been dubbed “Murinus,” a “fictional near-peer adversary on the north-eastern flank of the Alliance,” it's clear that the manoeuvres are rehearsal for a potential conflict with Russia.

They follow the massive Vostok exercises Russia held along its eastern borders last month. The defence ministry claimed that they included 300,000 troops, the country's largest war games ever.