The Princess of Wales’s parents joined thousands of racegoers at Royal Ascot for a day at the races as their daughter continued her cancer treatment.

Carole and Michael Middleton smiled and looked relaxed when they walked though the gates of the famous Berkshire meet, dressed for a day in the royal box.

It is believed to be their first appearance at a major event since it was announced in March Kate had began a bout of chemotherapy, following abdominal surgery in January.

Kate revealed in a statement on Friday she is making “good progress” in her treatment but candidly said she has “good days and bad days” and although there has been some limited working from home, she stressed “I am not out of the woods yet”.

The Prince of Wales is expected to attend Royal Ascot, as he is named in the official programme as handing out the prizes for the aptly named Prince of Wales’s Stakes, and the Middletons are likely to join him in the royal box.

Kate’s parents are thought to have been supporting their daughter during her months of receiving treatment for an undisclosed form of cancer.

Also presenting trophies to the winning jockeys, horse owners and trainers will be Princess Eugenie and BBC Gardeners’ World presenter Rachel de Thame.

The sight of the traditional carriage procession along the course brought a cheer from the crowds in the stands and riding with Queen Camilla was William and the Earl and Countess of Halifax.

Other guests included Andrew Lloyd Webber who was made a Knight Companion of the Order of the Garter during a ceremony at Windsor Castle on Monday, attended by the King and Queen and other senior royals.

Theatre impresario Lord Lloyd-Webber, whose hit musicals include The Phantom Of The Opera, Cats, Jesus Christ Superstar and Joseph And The Amazing Technicolor Dreamcoat, was joined by his wife.

Eugenie and husband Jack Brooksbank were in another carriage, and when the procession reached the parade ring, Zara Tindall was waiting to greet them all.

The Middletons also made their way into the ring to mingle with other guess from the royal box, but missing was the king, who wax pictured earlier performing duties of state.