A NATO training exercise expected to involve more than 4000 people has kicked off in the Outer Hebrides.

The military operation going by the name of Formidable Shield will run from May 8-26 and involve personnel from 13 Nato allied and partner nations.

More than 20 ships and 35 aircraft will take part in the training, including F-35 fighter jets.

The Ministry of Defence’s Hebrides missile testing range sites on South Uist, Benbecula and St Kilda are also expected to be used in the exercise, which aims to simulate real-world conditions in the event of an attack on a Nato ally.

Royal Navy Rear Admiral James Morley, who is serving as the Officer In Charge of the exercise, said Formidable Shield displays the “mutual commitment” of Nato nations to defence.

“Formidable Shield is the premier IAMD (Integrated Air and Missile Defence) and live fire rehearsal in the European theatre, and highlights STRIKFORNATO’s proficiency in seamlessly integrating Allied and partner maritime and air forces into combined operations.

“The strength and unmatched cohesion of our trans-Atlantic alliance, now at 31 members with the addition of our capable Finnish allies, lies in our mutual commitment to one another and to the deterrence and defence of the Euro-Atlantic area.

“This commitment shines through in complex, high-end evolutions like Formidable Shield.”

Dozens of live fire rehearsals will be held against subsonic, supersonic and ballistic targets, involving seafaring vessels, ground forces and aviation forces.

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Formidable Shield was first held in 2017 and has since become a regular event in Nato’s training calendar, taking place every other year.

“The early iterations of Formidable Shield focused on maritime Ballistic Missile Defence,” said Captain Jon Lipps, the US Sixth Fleet’s Commander and Officer in Tactical Control during the exercise.

“Today, we integrate joint capability from the ocean bottom to low earth orbit and span all domains to provide for the Deterrence and Defense of the Euro-Atlantic.

“Formidable Shield is not merely an exercise, it is the Alliance seamlessly demonstrating credible, collective deterrence and defence across all domains.”

It comes just weeks after it was revealed that a Russian ship stopped at wind farm sites in the North Sea off the coast of Scotland in order to gather intelligence and examine key energy sites for possible sabotage.