The Duke and Duchess of Cambridge along with Prince Harry will attend a service by the Archbishop of Canterbury to rededicate the grave of Princess Diana.

With the 20^th anniversary of her death just two months away, the commemoration service on Saturday will take place at her family home of Althorp House, Kensington Palace said yesterday.

The Prince of Wales will not attend as he in Canada for the 150th anniversary of the confederation of Canada.

Rededication services are highly unusual in the Church of England especially when there has been no change to the grave.

However it is not unprecedented and church figures have suggested the service will include prayers and reflection.

Prince William was 15 and Harry 12 when their mother was killed in a car accident in Paris on August 31, 1997.

The brothers have commissioned a statue to commemorate the 20^th anniversary which will be placed in the gardens of Kensington Palace, where the royal used to live.

Celebrations to remember her are expected to continue throughout the summer and includes a redesign of the island in the ornamental lake known as Oval in Althorp Park's Pleasure Garden where Diana is buried.