Keen to return to the front lines despite fears he would be a top Taliban target, Harry retrained as a helicopter pilot and served in Afghanistan in 2012-2013 as an Apache co-pilot gunner.

Most recently he has served as a staff officer in the army's London headquarters, playing a big role in bringing the Invictus Games - an international sports competition for wounded troops - to Britain.

Kensington Palace said that after leaving the army Harry will volunteer with the British military's Recovery Capability Program, which helps wounded service members, "while actively considering other longer-term employment opportunities."

Harry was the first British royal to see combat since his uncle, Prince Andrew, who flew Royal Navy helicopters during the 1982 Falklands War.

His older brother Prince William also attended Sandhurst before training as a Royal Navy search-and-rescue helicopter pilot. He has since left the navy to become an air-ambulance pilot.

Harry has often seemed more comfortable as a soldier than in his royal duties, although he has been visibly energized by his work with charities for wounded veterans.

"It's very easy to forget about who I am when I am in the army. Everyone's wearing the same uniform and doing the same kind of thing," Harry said in an interview after returning from Afghanistan in 2013.