The Prince of Wales and the Duchess of Cornwall are to meet Pope Francis at the end of March or at the beginning of April.
The Duchess and Prince Charles
Clarence House has confirmed the British royals will meet the Pope as part of of a wider European tour - which will include their first private tour of the Vatican.
However, Clarence House has been unable to confirm a specific date for the tour, merely announcing that it will take place at some stage between March 31 and April 5.
Prince Charles' European tour will also see the royal visit Romania and Austria, and will come amid Britain's exit from the European Union - an issue which the Vatican has taken a keen interest in.
Confirmation of the royal visit comes shortly after biographer Penny Junor claimed Prince Charles will "push" for his wife to be given the title of Queen when he becomes the King.
She argued that the 68-year-old royal is determined to ensure his wife will be named Queen, despite potential opposition to the move on account of her status as a divorcee and the public affection for Princess Diana, Charles' first wife.
She said: "Charles will push for this. He is so fiercely proud of her and I think would see anything less than the title of Queen as being a slight. And he has never been good at taking advice from people that disagree with him.
"But she has no desire to be Queen. She got into this position because she loved him and wanted to support him in his otherwise lonely role; she didn't marry him because she wanted to be a Duchess or a Princess or even a Queen.
"But it is a very difficult subject because there will always be people who say that to make her Queen would be to reward adultery."
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