Maj Gen Bruno Beeckmans, commander of the Belgian air force, said the aircraft were providing a 24-hour quick reaction alert capability and would train alongside Nato maritime, special forces and other air assets.

“We’re very delighted to bring our professional air power as a part of the Nato contribution to protect,” he told the Telegraph.

But Iceland is not simply relying on its allies. Its civilian institutions are increasingly being forced to perform roles normally associated with a military.

Describing Keflavik airbase as the “eyes and ears of the North”, Marvin Ingólfsson, the base’s deputy commander, said the work there was becoming increasingly militarised.

“Iceland has no standing officers of course. But we have the national police, we have the coast guard and we are basically conducting jobs that you can see a military doing. And of course, many of us here have, in a way, military training.”

The Icelandic Coast Guard has 280 officers and operates two offshore patrol vessels. It also operates Iceland’s air-defence system, with four radar complexes positioned around the island to monitor the country’s airspace.

Jónas G Allanson is head of the defence office at the country’s ministry of foreign affairs, essentially acting as the country’s minister of defence. He said he was increasingly concerned by Russian submarine activity.