It has tech billionaires, A-list celebrities, a sun-soaked programme of work and play and a top-secret itinerary known only to an elite few.

This year’s Google Camp, nicknamed “Davos by the sea” for its habit of convening a guest list of power, money and influence, also boasted the attendance of the Duke of Sussex, it has been claimed.

The Duke delivered a “bare foot speech” on the topic of climate change and conservation to celebrities, entrepreneurs and high-flying business leaders, reports say, describing his words as “impassioned”.

The reports, which have not been denied by the palace, said the Duke had shared the same sentiments he has offered in recent public speeches and his interview with Jane Goodall in British Vogue, imploring his audience to save the world.

Guests at the exclusive Google Camp on the south-west coast of Sicily have been accused of hypocrisy after an estimated 114 private jets and numerous superyachts were used to ferry them to and from sessions about the most pressing issues facing the planet.