The Prince and Princess of Wales surprised guests as they enjoyed a date at Tuesday's Buckingham Palace garden party.
William, 40, donned a morning suit and top hat, while his wife Kate, 41, looked beautiful in a powder blue Elie Saab dress and a matching Philip Treacy hat, first worn to Royal Ascot in 2019.
They were also joined by the Duke and Duchess of Edinburgh, the Princess Royal and the Duke and Duchess of Gloucester.
Sophie, 58, matched Kate in a blue outfit, while Anne, 72, opted for a cream ensemble. See the royal arrivals at the garden party in the clip below...
The couple mingled with around 8,000 guests at the palace, with a military band playing background music. Guests enjoyed cups of tea, sandwiches and slices of cake, while taking a stroll around the gardens.
Garden parties have been held at Buckingham Palace since the 1860s when Queen Victoria began what was known as “breakfasts”, although they took place in the afternoon.
Prince Edward, 59, also donned a morning suit with a pink tie, while his wife Sophie, opted for a blue dress by Suzannah London and a Jane Taylor hat.
Kate accessorised her lace blue dress with metallic accessories, including an Elie Saab clutch and her Kiki McDonough topaz hoop earrings.
Kate, who is joint president of the Scouts, was buoyed by polling that suggested almost six million people had got involved in volunteering during the Big Help Out on Monday and many were ready to do more with organisations.
"You must be thrilled. It was a wonderful turnout," she told Graeme Hamilton, a lead volunteer with the Scouts, which has half a million children as members in the UK but thousands more on waiting lists to join if more adult volunteers can be found to help.
She added: "It's so great getting young people involved in helping others."
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The Princess Royal had a starring role at the King's coronation on Saturday as the monarch's Gold-Stick-In-Waiting, and she rode on horseback during the carriage procession.
While Anne and her husband, Vice Admiral Sir Tim Laurence also attended events for the Big Lunch and the Big Help Out, they were noticeably absent from the coronation concert.
Anne's two children, Peter Phillips, and Zara Tindall, and their respective spouses, Lindsay Wallace and Mike Tindall, were among the guests in the Royal Box at Windsor Castle for the bash.
Take a look back at what the Prince and Princess of Wales have been up to over the last few days...
It follows a busy few days of public outings for the Waleses who attended the King and Queen's coronation at Westminster Abbey on Saturday.
The Prince was the only member of the royal family tasked with paying homage to the King during the ancient coronation ceremony, as he knelt before his father, touched his crown, kissed him on the cheek and vowed to be his “liege man of life and limb".
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At the coronation concert at Windsor Castle on Sunday evening, William also paid a touching tribute to his father Charles, saying on stage: "Pa, we are all so proud of you."
Earlier that day, William and Kate surprised revellers at a big lunch street party on the Long Walk in Windsor.
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And on Monday, the Prince and Princess of Wales and their three children helped out at a Scout Hut in Slough as part of the national volunteering drive to mark the coronation.
It marked a milestone for five-year-old Prince Louis as he got stuck into a spot of painting, digging and decorating during his first ever official royal engagement.
Prince George, nine, and Princess Charlotte, eight, also joined their parents at the concert, where the youngsters were spotted singing along to the performances, with Lionel Richie's song All Night Long prompting all of the royals on their feet to dance. The Duchess of Edinburgh was even captured showing off her moves.
Meanwhile, William and Kate were among the working royals to feature in a series of official coronation portraits released by the palace on Monday.
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