William and Harry view tributes left in memory of Diana at Kensington Palace

The Duke of Cambridge and Prince Harry have made a personal pilgrimage to view the floral tributes left in memory of their mother as Harry confessed "all of us lost somebody".

William and Harry stopped to look at the heartfelt messages, pictures and flowers left in remembrance of Diana, Princess of Wales at the gates of her former home Kensington Palace.

The 20th anniversary of Diana's death will be commemorated on Thursday and the royal brothers, with Kate, earlier honoured her memory by visiting a nearby memorial garden in the grounds of the palace created for the Princess.

Charity chiefs from organisations associated with Diana met the royals after their tour and Harry told one group of campaigners about how his mother's death was a tragedy for them - as they were preparing to work with the royal - as well as his family.

He said: "I can imagine for a lot of you it was like 'right here we go, now we've got her, we've got the thirst, we've got the attention, now let's do something' then suddenly she's snapped away - if I can put it (this way) all of us lost somebody."

The royal brothers had spent an hour touring the temporary memorial White Garden in the grounds of the palace with Kate before making the short journey to the gates, which is fast becoming a shrine to their mother.

Sheltering from the heavy rain under an umbrella William knelt down to look at some of the bouquets left in tribute to his mother then later pointed out a picture to his brother that appeared to make him laugh.

Harry came over to have a look at the picture which had left his older brother in stitches and William said: "Look at my shades". The Prince glanced at the photograph of the Duke and his mother both wearing sunglasses as they sat in the crowds at an unknown event.

The Duke and Prince stood together under their umbrellas looking at the lovingly created picture montages of Diana that sometimes featured them as babies, toddlers and young boys.

The royal siblings have talked candidly about the loss of their mother in a number of documentaries and interviews this year, and about the scenes they experienced when they came to see the tributes left at Kensington Palace a few days after their mother's death.

William reminisced about that moment and took a few moments to point out to Harry how far back the flowers had stretched from the gate.

Pointing out where the sea of 1997 tributes had stretched to, he said: "Last time, it was all the way down." Noting a large display of photographs, he added: "They've put a banner up."

William and Harry's appearance had attracted several hundred well-wishers who lined crash barriers and the brothers each placed a floral tribute at the gates for fans of their mother.

Sisters Gracie, aged eight, and Maisy Oxby, 10, from Basildon in Essex handed over a bouquet of red blooms to Harry to place at the entrance on behalf of another royal fan.

Maisy said: "He took the flowers and asked us who we were and said 'whereabouts would you like them to go'? I said in the middle under the HRH on a poster."

Her sister added: "A lady gave us the flowers and she said can you give it to one of the princes."