King Charles and Queen Camilla are celebrating their 20th wedding anniversary in Italy today, having tied the knot on April 9, 2005. But a former BBC royal correspondent believes that back in the 1990s it would have seemed "ludicrous" to imagine the public would have been swayed by their love for one another.

Royal expert, Jennie Bond, told Express.co.uk: "For anyone under the age of about 30, it must be almost impossible to appreciate how extraordinary it is that Charles and Camilla have been able to enjoy two decades of wedded bliss."

She added: "Back in the 90s, it seemed ludicrous to imagine that public opinion would ever allow them to live together, let alone marry and for Camilla to be crowned Queen. That they’ve been able to do so is testament to the deep love the King has for his wife and his stubborn refusal to bow to pressure and give her up."

The King and Queen will mark their 20th wedding anniversary as the guests of honour at the traditional state banquet. Charles and Camilla will be joined by prominent figures from Italian society at the black-tie dinner hosted by Italy’s President Sergio Mattarella. It will be held at the Quirinale, which is a former Italian palace and one of the official residences of the President of the Republic.

To mark the royal couple's special wedding anniversary, Buckingham Palace released three snaps of the King and Queen in new pictures taken outside Villa Wolkonsky, the ambassador's residence where they are staying for the duration of their trip. The three images, released on Monday evening, show the royal couple next to the Neronian spur of the Aqua Claudia.

One picture shows the couple arm in arm beaming at the camera, while another shows Charles affectionately looking at his wife. A third portrays the pair with their arms around each other, while sitting on a bench. Camilla is wearing a white and beige coat dress by Anna Valentine and a Lily of the Valley brooch - a symbol of enduring love.

The couple's visit to Italy, which will conclude on Thursday, April 10, will be carried out on behalf of the Foreign and Commonwealth Office to strengthen post-Brexit relations between Rome and London.

The then Prince of Wales married Camilla Parker Bowles in a civil ceremony at Windsor Guildhall in 2005.

Their low-key wedding was then followed by a Service of Prayer and Dedication at Windsor Castle, which the late Queen Elizabeth II and Prince Philip and wider members of the Royal Family attended.

Camilla wore two outfits on her wedding day, designed by Antonia Robinson and Anna Valentine. The first dress for the civil ceremony was a knee-length cream dress with a feathered hat by Philip Treacy. The bride then changed into a floor-length embroidered pale blue and gold coat over a matching dress and accessorised with gold feathers.