LONDON (AFP) ― Prince William’s wife Kate joined the queen and mother-in-law Camilla for a tour of upmarket store Fortnum and Mason on Thursday, sampling tea and sweets before taking home some dog biscuits.

The duchess of Cambridge, wearing a blue coat dress by Italian designer Missoni, joined Queen Elizabeth II and Prince Charles’ wife in the trio’s first official engagement together at the London shop known as the queen’s grocer.

The three women were presented with wicker hampers filled with luxurious items, and Kate burst into giggles when she discovered “hearty treats for happy hounds” in hers ― a gift for her cocker spaniel, Lupo.

“Of course they all have dogs and we do want to think about what our customers like,” said Fortnum’s managing director Beverley Aspinall.

Kate and Camilla enjoyed a tour of the shop floor, while the queen, wearing a blue Angela Kelly suit, looked at the honey and preserves.

Outside on London’s famous Piccadilly, crowds lined the pavements to catch a glimpse of the royal ladies, although a animal rights campaigners also gathered to protest the store’s policy of selling foie gras, with one activist dressed up as a goose.

Among the dignitaries present was London mayor Boris Johnson, who discussed with Kate the tandem bicycle he gave her and William for their wedding last year.

According to the Evening Standard newspaper, the duchess revealed that the royal couple had tried it out in the garden of their official London residence, Kensington Palace, but had yet to brave it in the street.

Prince William, a helicopter search and rescue pilot with the Royal Air Force (RAF), is currently on deployment in the Falkland Islands. He is normally based in Wales, where the couple live.