Queen Camilla wore black to meet Pope Francis at the Vatican, but why can Princess Charlene and other royal women wear white? All about the royal rule and fashion choices past.

King Charles III and Queen Camilla met with Pope Francis Wednesday in Vatican City to mark their 20th wedding anniversary.

After being discharged from the hospital two weeks ago, Pope Francis held a private audience with the royal couple and shared his “best wishes” as they celebrate two decades of marriage.

King Charles and Queen Camilla have left Italy after a four-day state visit. They ended the trip with a celebration of the country's food, trying their hand at making pasta at a festival in Ravenna. The visit had included a brief private meeting with Pope Francis in the Vatican,

King Charles III and Queen Camilla met privately with Pope Francis on Wednesday in the Vatican, Buckingham Palace said, just weeks after Francis spent more than five weeks in the hospital.

King Charles and Queen Camilla have had a private meeting with Pope Francis at the Vatican where he wished them a happy 20th wedding anniversary. In a statement released by Buckingham Palace, the King and Queen said they were "delighted the Pope was well enough to host them - and to have had the opportunity to share their best wishes in person".