A leading royal expert has claimed that King Charles became a “nicer” person after he married Queen Camilla two decades ago. Top royal photographer Arthur Edwards has captured the Royal Family for over 50 years and has had more insight into what the royals are like behind closed doors than most.

Speaking ahead of King Charles and Queen Camilla’s milestone 20th wedding anniversary which will be marked in Rome on Wednesday, Mr Edwards said that he has seen the couple’s marriage up close and knows it is a “happy union”, adding that the King became “nicer” when he was finally allowed to marry Camilla.

Writing for The Sun, the royal photographer said: “I have seen their marriage up close and, in my opinion, it is an extremely happy union.

“Since their wedding in Windsor on April 9, 2005, it has become very obvious that they make each other feel very happy and secure.

“The main thing I’ve noticed is that the King, who I have been photographing for nearly 50 years, has become a nicer person. Thanks to Camilla, he has calmed down. These days he rarely gets stressed or wound up about things.”

He continued: “In the past he would get angry if the windows were shut or there was no air in the room. All that pent-up anger seemed to disappear after he tied the knot with Camilla.

“Occasionally, like the time when his pen leaked during an official ceremony, he will become a bit frustrated, but Camilla soothes the situation.”

Their Majesties will be spending their 20th wedding anniversary in Italy this week for a state visit.

On the evening of their anniversary, they will be treated to a lavish state banquet held in Rome, where they 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, a former Italian palace and one of the official residencies of the President of the Republic.