The King and Queen's state visit to the Vatican has been postponed by mutual agreement as the Pope recovers from illness, Buckingham Palace said.
The Pope, 88, arrived home to the Vatican on Sunday after spending five weeks in hospital battling a life-threatening bout of pneumonia.
A statement said, "medical advice has now suggested that Pope Francis would benefit from an extended period of rest and recuperation".
Charles and Camilla's tour of Italy is understood to still be going ahead, however, there are expected to be some changes to the programme, which was announced in March.
The trip from 7-10 April was set to celebrate the papal jubilee and the relationship between the Catholic Church and the Church of England.
"Their Majesties send The Pope their best wishes for his convalescence and look forward to visiting him in The Holy See, once he has recovered,'' the palace said in a statement.
Pope Francis, who had been at Rome's Gemelli hospital since 14 February, was discharged on Sunday.
Before he left, he appeared on a public balcony at the medical centre to bless the crowds.