The Queen and Prince Philip are among the guests at a special commemoration service honouring those who fought in Afganistan.
The royal family joined civil dignitaries, politicians, serving British forces personnel, veterans and families for the service at St Paul's Cathedral.
A total of 453 personnel and Ministry of Defence staff lost their lives in the conflict, which began in October 2001.
The Duke and Duchess of Cornwall are among the members of the royal family attending today's remembrance service for British servicemen and women that fought in Afghanistan.
Charles and Camilla arrived shortly after the Duke and Duchess of Cambridge and just before the Queen.
The Duke and Duchess of Cambridge have arrived to pay their respects to those who fought during the Afghanistan operation.
Prince William and Kate joined other members of the royal family, politicians, and dignitaries for the special commemoration service, as well as serving forces personnel, veterans and families.
St Paul's Cathedral has shared images of the grand venue's preparations for today's special service honouring Afghanistan veterans.
Veterans of the Afghanistan conflict have paid tribute to those they left behind after leaving the warzone.
Evans served as a gunner in Afghan: "When I finished my tour, I couldn't help to think of my friends still serving." http://t.co/lyJWec87rk
Former Labour Prime Ministers Tony Blair and Gordon Brown have arrived at a special service honouring British forces personnel who died during the Afghanistan campaign and veterans who survived the conflict.
Brown arrived shortly after Blair at St Paul's Cathedral, London, where the service is being held.
A special service honouring the 453 British forces personnel who died during the Afghanistan campaign and the veterans who survived the conflict is being held in London today.
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The President of Afghanistan, Ashraf Ghani, has paid tribute to Britain's 453 war dead ahead of a special service honouring troops.
Speaking to the BBC, President Ashraf Ghani the service personnel had "paid the ultimate sacrifice to enable us to live in freedom, in hope for peace, prosperity and dignity".
A commemoration service will today honour the 453 British forces personnel and Ministry of Defence workers who died, or are missing presumed dead, while serving in Afghanistan.
Operations in the country began in October 2001.
Among those to be honoured today will be five serving soldiers killed in a helicopter crash in April last year.
Capt Thomas Clarke, aged 30, from Cowbridge, of the Army Air Corps; Wt Ofcr Spencer Faulkner, 38, of the Army Air Corps; Cpl James Walters, 36, from Cornwall, of the Army Air Corps, were serving as the Lynx aircraft's three-man team when they died.
Flt Lt Rakesh Chauhan, 29, from Birmingham, of the Royal Air Force; and Lc Cpl Oliver Thomas, 26, from Brecon, of the Intelligence Corps, were passengers on the flight.
The families of soldiers killed in Afghanistan and veterans of the 13-year campaign will march past St Paul's Cathedral in a parade following today's commemoration service.
Members of the Royal Family will later meet those who took part in the commemorations or served in Afghanistan during a series of receptions.
Similar services will also be held at military bases, cathedrals and churches across the country, as well as in Germany for personnel serving there.