King joined by the Beckhams as Highgrove becomes Italian restaurant for the night

Helen Mirren and the Beckhams were among the King’s guests at a black tie dinner to celebrate Anglo-Italian relations.

David Beckham, the former England footballer who was twice loaned to AC Milan, and his wife Victoria joined Donatella Versace, the Italian fashion designer, and Mirren, the Oscar-winning actress, at Highgrove, the monarch’s Gloucestershire home, on Friday evening.

Beckham was last year announced as an ambassador for the King’s Foundation, the charity that runs Highgrove, while he and his wife own an estate nearby in the Cotswolds.

Stanley Tucci, the Italian-American actor, was also among the 80 guests gathered for the unique meal designed to champion both the importance of homegrown, seasonal British produce and authentic Italian flavours.

In a short speech, the King expressed delight that his “niche” passion for slow food was finally gathering momentum as he described how food choices helped to define cultures and bring people together.

He warned that the way food was produced was “intimately entwined” with the future of the planet.

Also among the guests was Carlo Petrini, the food writer who founded the slow food movement in Italy in 1986 after campaigning against the opening of a McDonald’s in Rome’s Piazza di Spagna.

The King’s passionate defence of the movement came more than two decades after he delivered a landmark speech in Turin, Italy, in which he warned that the “industrialisation of agriculture and the homogenisation of food” had “invaded almost all areas” of modern life.

He said: “I can scarcely believe that it is over twenty-one years since I spoke at Carlo Petrini’s Terra Madre conference in Turin – dedicated to the cause of slow food which Italians have long pioneered.

“I am delighted that in the intervening two decades, a subject which was perhaps a niche interest is now at the heart of discussions about a sustainable future for our planet.”

The monarch has long been friends with Mr Petrini after they bonded over their shared passion for all things organic and their mutual determination to shift public attitudes over food.

The Italian activist once said he considered Charles “the patron of the slow food movement, our spiritual guide”, describing him as a “visionary”.

He said in 2007: “People thought he was just romantic, a poet, and that his approach wouldn’t have any economic impact; but his way is the only salvation for the planet.”

For his part, the King has paid tribute to Mr Petrini’s “extraordinary vision and indomitable spirit”, which he said had helped to “begin a revolution which will benefit small farmers the world over”.

Tucci and his friend, Calabrian chef Francesco Mazzei, painstakingly designed a menu for the King’s event that was a masterclass in culinary diplomacy.

While each course was traditionally Italian, almost every ingredient was produced in Britain, painstakingly sourced over many months from Scotland to Somerset.

Guests dined on canapes including Yorkshire Pecorino cheese puffs and British vegetables, caponata tartelletta, Scottish crab panzanella, ravioli made with Westcombe ricotta and Suffolk red porchetta.

The King, who can speak several languages, spoke briefly in Italian as he welcomed them to Highgrove, describing how the event brought together “two things very dear to my heart – slow food and Italy”.

“Our two nations share so many ties – between our peoples; between our cultures; a deep friendship rooted in shared values, mutual affection and mutual respect,” he said.

“A nation’s food culture is a priceless social and environmental asset, intimately bound up with its sense of identity and place.

“Good food brings people together and what we choose to eat helps to define us – as families, communities and nations. It brings us sustenance, but also comfort. It binds generations, as recipes are passed down from one to another. It is a thing of beauty – ‘edible art’, as you have put it, Stanley!”

The King was seated between Italian ambassador Inigo Lambertini and Tucci’s wife Felicity Blunt, the sister of actress Emily Blunt, while the Queen sat next to Tucci.

The tables were laden with fresh seasonal flowers and napkin rings made by student milliners on King’s Foundation courses.

Mr Mazzei said he had poured heart and soul into the menu, travelling the length and breadth of the UK to source every ingredient before compiling a detailed report for the royal chef and urging him to show it to the King.

“I was in Devon two weeks ago to get the salumi,” he said. “I went to see the pigs where the belly comes from.

“The tomatoes for the passata are from the Isle of Wight. The cob nuts for the biscotti are from Kent.”

Meanwhile, mixologist Alessandro Palazzi served James Bond-inspired martinis.

The event came ahead of the King and Queen’s state visit to Italy and the Vatican in early April, when they will undertake engagements in both Rome and the north eastern city of Ravenna, known for its early Christian mosaic artwork.

The couple will meet the Pope at the Vatican and celebrate the Catholic Church’s Pilgrims of Hope jubilee year, attending the Holy See, the government of the Roman Catholic Church.

The King said that to say they were looking forward to the visit “would be to engage in a little British understatement…”

He proposed a toast to “Italy’s timeless food culture, so loved here in the United Kingdom and across the world”.