Members of the Household Cavalry will be among those on duty at the royal wedding on 19 May.
Soldiers from the mounted regiment will form a step-lining party at St George’s Chapel, Windsor Castle, when Prince Harry marries Meghan Markle, while the state trumpeters and a travelling escort from the regiment will also provide “ceremonial support”.
Members of units with which Harry has a “special relationship” will be performing ceremonial duties at the wedding.
More than 250 members of the armed forces will take part.
A Kensington Palace spokesman said: “Prince Harry and Meghan Markle are pleased that members of the armed forces will play such a special role in their wedding.
“The military, and these units in particular, hold a great significance for Prince Harry and the couple are incredibly grateful for their support.”
After his commission at the Royal Military Academy Sandhurst, Prince Harry joined The Blues and Royals (Royal Horse Guards Dragoon), Household Cavalry Regiment in April 2006, undertaking two tours of Afghanistan and rising to the rank of captain.
He is commodore-in-chief of the Royal Navy Small Ships and Diving, captain general of the Royal Marines and honorary air commandant of RAF Honington, all of which will be represented lining the streets near the castle.
Also on duty will be personnel from the 3 Regiment Air Corps and the Royal Gurkha Rifles, with both of which the prince served in Afghanistan.
Air Chief Marshal Sir Stuart Peach, chief of the defence staff, said: “I am proud that members of the armed forces have been asked to take part in the ceremonial celebrations taking place on the royal couple’s wedding day.
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“It is a happy occasion for the whole country and reminds us of the role the armed forces play in marking important events in the life of the nation.
“I am particularly pleased to hear that members of the armed forces who have a close relationship with Prince Harry will be taking part. Servicemen and women from the Royal Navy, Army and Royal Air Force will all be honoured to offer their support.”
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