Operation ‘Highmast’ gets underway as UK carrier strike group forms for eight-month deployment

The UK’s premier naval deployment of 2025 got underway on 22 April when the aircraft carrier HMS Prince of Wales departed Portsmouth, followed a few hours later by the destroyer HMS Dauntless.

HMS Prince of Wales is leading an eight-month mission of Carrier Strike Group 25 known as Operation ‘Highmast’, under which series of exercises and operations will be conducted with air, sea and land forces of a dozen allies in the Mediterranean, Middle East, South-east Asia, Japan and Australia.

International by design, the task group will be joined in the English Channel by two Norwegian vessels, the tanker HNoMS Maud and frigate HNoMS Roald Amundsen, coming directly from Norway, with the Royal Navy frigate HMS Richmond and Royal Canadian Navy frigate HMCS Ville de Québec sailing from Plymouth. The Royal Fleet Auxiliary tanker RFA Tidespring, which has spent much of 2025 in Birkenhead undergoing maintenance and upgrades to prepare for the mission, will complete the strike group in its initial format.

By the end of April Carrier Strike Group 25 will have embarked up to 24 British F-35B Joint Strike Fighters and squadrons of attack, troop-carrying and anti-submarine helicopters, along with unmanned aerial vehicles, all supported by around 750 personnel in the air wing alone.

The deployment will initially begin with around 2,500 military personnel in total – around 2,100 Britons, 200 Norwegians and a similar number of Canadians and Spanish – but this personnel strength will rise to over 4,500 for some of the key exercises as the force reaches the Indo-Pacific.

Operation ‘Highmast’ will be commanded by Commodore James Blackmore and his staff from aboard HMS Prince of Wales. Cdre Blackmore was quoted in a Royal Navy press release as saying, “I am delighted to lead the UK Carrier Strike Group encompassing sailors, marines, soldiers and aviators from across the UK and allied armed forces. Working closely with partners from across the globe, Operation ‘Highmast’ will demonstrate credible deterrence and our support to NATO and the rules-based international order.

“This will reaffirm that the UK is secure at home and strong abroad and reinforce the UK’s commitment to the Indo-Pacific,” the commodore added.

This is the second deployment of a UK Carrier Strike Group in the modern era. The first, led by HMS Queen Elizabeth in 2021, took place against the backdrop of a world in lockdown due to the Covid pandemic.