The King will not carry out royal engagements for up to a month as he recovers from surgery in hospital, Sky News understands.
The King underwent a procedure for an enlarged prostate on Friday at The London Clinic.
He remains in hospital – with the Queen telling patients that he is “doing well” during a visit.
Sky’s royal correspondent Laura Bundock says there will be a “period of recuperation” for the King – adding that he will be available for state matters while in hospital and is able to attend to red boxes with government papers when he is discharged.
The Princess of Wales is also currently staying at The London Clinic having undergone abdominal surgery.
“His Majesty would like to thank all those who have sent their good wishes over the past week and is delighted to learn that his diagnosis is having a positive impact on public health awareness,” Buckingham Palace said in a statement on Friday.