The Duke of Cambridge has written a cheeky dedication to Sweden’s Crown Princess – on a high-tech bag.

With his wife Kate nearby, William made the heir to the Swedish throne laugh when he chose the message “I belong to Victoria” to appear on the item via Bluetooth.

Crown Princess Victoria has been getting to know Britain’s future king during his tour of Stockholm, joining the Cambridges for much of their visit with her husband Prince Daniel.

William and Victoria were shown the high-tech bag when the royal foursome visited one of the Swedish capital’s busiest shopping centres to open an interactive exhibition of UK design, fashion and brands that operate in the Nordic country.

The exhibition’s theme was sustainability and innovation – with everything from vegan shoes to Bluetooth-operated bags on display.

Francesca Rosella and Ryan Genz, who founded company Cutecircuit in 2004, spoke to William about their bags that can be customised via a smartphone through Bluetooth technology to display any message or pattern.

Francesca said about William: “He said it was very clever. He really understood how everything worked. He seemed passionate about technology.”

Given the opportunity to choose a message for the bag, William wrote “I belong to Victoria”, at which the group laughed.

Ms Rosella said Crown Princess Victoria found the message “very funny”.

Victoria is the modern, approachable and down-to-earth face of the Swedish monarchy who married her personal trainer Daniel Westling after a long period as a couple like William and Kate.

They now have two children, five-year-old Princess Estelle and one-year-old Prince Oscar, with Prince Daniel a house husband.