Unseen childhood photos of Princess Diana with her sons published to mark anniversary of her death.

Never-seen-before photographs of princes William and Harry as children have been published to coincide with the release of a new documentary about Princess Diana on the 20th anniversary of her death.

The pictures have been taken from Diana’s personal photo albums which were recently discovered by her sons who are shown in a TV documentary flicking through them.

A sun-kissed image showing Diana hugging Harry while the pair are on holiday, is just one of the poignant pictures that are featured in the TV program.

In the ITV documentary, Diana, Our Mother: Her Life and Legacy, William says to Harry about the photo: “This one here, I thought you’d like to see – quite a special picture – the two of you which I thought was quite sweet”.

The photo shows Harry apparently wearing just trunks and sitting down with his legs up against his chest while his mother’s arm is wrapped around his neck.

Harry joked about the image saying: “I just remember having the skinniest legs, and still do”.

Harry admits “part of him” did not want to look at them but he was also waiting for the right time to sit down with his brother and go through the pictures.

The Duke and Prince Harry are pleased to share three photographs from the personal photo album of the late Diana, Princess of Wales that feature in the new ITV documentary ‘Diana, Our Mother: Her Life and Legacy.’ The 90-minute film, made by Oxford Film and Television, celebrates the life and work of Diana, Princess of Wales in the 20th anniversary year since her passing. In the documentary, The Duke and Prince Harry recall fond memories from their childhood as they look through photographs in a family album assembled by the late Princess. ‘Diana, Our Mother: Her Life and Legacy’ will air on @itv at 9pm on Monday 24th July.

A post shared by Kensington Palace (@kensingtonroyal) on Jul 23, 2017 at 12:11am PDT

Another of the featured photographs shows Harry sitting on a picnic bench while William sits directly behind him on the table.

And a third image shows a pregnant Diana holding a toddler William on her hip as the pair pose for the picture.

In the 90-minute program William said: “She loved taking pictures, it was so nice. She captures some really good portraits of people, you kind of get a snapshot of the personality quite quickly.

“The funny thing is there is not that many of her, as she is always taking pictures of us.”

The documentary, Diana, Our Mother: Her Life and Legacy will be screened in the UK on ITV on Monday