Diana's wedding dress is highlight of royal style exhibition - thanks to Princes

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Princess Diana's wedding dress has gone on display for the first time in 25 years after her sons gave permission for it to form part of an exhibition on royal style.

Royal Style in the Making opens at Kensington Palace on 2 June, and also includes the late princess's going away outfit after her wedding, and the Queen's coronation gown.

Diana's wedding dress was made by David and Elizabeth Emanuel, of ivory silk and pure taffeta, with 10,000 pearls, and a 25ft train.

It has been part of the private collection of Princes William and Harry and a previous curator at Historic Royal Palace revealed that meant it would not be going on display unless the brothers agreed.

It is not clear when the brothers gave their permission, but the exhibition was only announced at the end of April. However, Historic Royal Palaces said they have been hoping to display the dress since 2017.

William, 38, and Harry, 36, issued separate statements at the same time about their mother following the release of a report into the way Martin Bashir was able to secure a BBC interview with the late princess in 1995.

However while they were both critical, there was little in common about the statements, and they were previously said to have broken the ice but not made any progress in their rift.

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Historic Royal Palaces said in a comment on the exhibition: "The dress, on loan from HRH The Duke of Cambridge and HRH Duke of Sussex, is now among the most famous in bridal history, and features a fitted bodice overlaid at the centre both front and back with panels of antique Carrickmacross lace that had originally belonged to Queen Mary, the groom’s great-grandmother.

"Its gently scooped neckline and large puffed sleeves are trimmed with bows and deep ruffles of taffeta, a style popularised by the Princess in the early 1980s, while the full skirt is supported on a mountain of stiff net petticoats to create its famous silhouette."

It was on display in Kensington Palace in 1995, and then at her childhood home of Althorp.

As well as garments, the exhibition features sketches from designers who have worked with royals over the years.

The exhibition promises to show the "intimate relationship between fashion designer and royal client" revealing the connection between commission and garment for some of the most famous pieces in royal history.

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Diana's pieces are not the only draw, as the exhibition also has a toile of Queen Elizabeth, the Queen Mother's coronation gown, and a dress of Princess Margaret's.

Queen Elizabeth, who became known as the Queen Mother after Queen Elizabeth II's accession in 1952, was crowned Queen Consort in 1937, and wore a satin gown with the national emblems, to show the continuity of the new king's reign.

HRP said the toile is an "extraordinary full-size working pattern of the completed gown, and features the stunning design for the embroidery hand-painted onto it, highlighting the attention to detail required in planning for such an important state occasion".

The Queen Mother died in 2002 at the age of 101.

Also on display is a blue Georgian style dress worn by Princess Margaret in 1964. Margaret was the Queen's younger sister, and also died in 2002, the same year as their mother.

The exhibition has other never-before-seen items and promises surprises for fashion fans.

Matthew Storey, exhibition curator at Historic Royal Palaces, said: "Our summer exhibition at Kensington Palace will shine a spotlight on some of the greatest talents of British design, whose work has been instrumental in shaping the visual identity of the royal family across the 20th century.

"We’ll be exploring how the partnership between each designer and client worked, and revealing the process behind the creation of a number of the most important couture commissions in royal history.

"While one of the highlights will undoubtedly be Diana, Princess of Wales’s show-stopping Emanuel-designed wedding dress – which goes on show at the palace for the first time in 25 years – we’ve got some real surprises up our sleeve for fashion fans."

It opens in Kensington Palace's Orangery on 3 June, and runs until 2 January 2022. It will be closed on 1 July, which would have been Diana's 60th birthday.

William and Harry are expected to reunite on that day to unveil a statue of her in the sunken garden of the palace. Kensington Palace has not commented on whether they will view the wedding dress.

Admission is included on entry to the palace.

Watch: David Emanuel reveals what Princess Diana was really like