The Princess Royal met the family of a senior aircraftman who died in Afghanistan after unveiling a plaque to commemorate those killed in conflict since the Second World War.

The widow of Senior Aircraftman Gary Thompson, who became the oldest British serviceman to die in Afghanistan when he was killed in April aged 51, attended a service at Westminster Abbey with her five teenage daughters.

The service was attended by Defence Ministers and Chiefs as well as 400 Service personnel who have served in Iraq and Afghanistan with the Royal Navy, the Army and the Royal Air Force.

The metal plaque in Westminster Abbey's South Cloister, which the Princess Royal unveiled before the service, is part of the Armed Forces Memorial which includes the National Remembrance Arboretum near Lichfield, opened earlier this year by the Queen.

The Princess Royal said the purpose of the memorial was "to remember the sacrifice and heroism in defence of freedom of the men and women who have lost their lives in conflict since the Second World War".

The plaque, designed by artist Tom Phillips, is made of welded steel and covered with earth gathered from battlefields across the world.

It reads: "Remember the men and women of the Armed and Auxiliary Forces who lost their lives in times and places of conflict since the Second World War."

A total of 16,000 men and women have been killed in conflict zones since 1945.

At the service, Anne and 17-year old Kelly Thompson, the youngest daughter of SAC Thompson, both gave a reading.

Speaking to the family after the service, the Princess Royal congratulated Kelly on her reading, saying: "It isn't an easy thing to do."