The King and Queen have postponed their visit to the Holy See because of medical advice that suggests Pope Francis will benefit from an extended period of rest, Buckingham Palace says.

The royals’ trip to the Vatican was scheduled to start on April 7, with a meeting with Pope Francis the following day.

Their subsequent trip to Italy will continue.

“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 statement said.

Pope Francis, 88, left hospital on Sunday, returning to the Vatican after surviving a five-week, life-threatening bout of pneumonia.

Earlier this week, the head of his medical team said the Pope came so close to death at one point during his 38-day fight in hospital against pneumonia that his doctors considered ending treatment so he could die in peace.

Sergio Alfieri, a physician at Rome’s Gemelli hospital, said that after a breathing crisis on February 28 that involved Francis nearly choking on his vomit, “there was a real risk he might not make it”.

“We had to choose if we would stop there and let him go, or to go forward and push it with all the drugs and therapies possible, running the highest risk of damaging his other organs,” he told Italy’s Corriere della Sera in an interview published on Tuesday.

“In the end, we took this path.”

Francis has been prescribed two more months of rest to fully heal.

It remains unclear how much he will be seen in public in coming weeks.

Recounting the Pope’s first public appearance since entering hospital, when Francis appeared on a hospital balcony to greet well-wishers on Sunday, Alfieri said that was the moment of Francis’s treatment that struck him the most.

“I saw him leave the room on the 10th floor of the Gemelli dressed in white,” the doctor said.

“It was the emotion of seeing the man become again the Pope.”

The cancellation of the meeting with the King comes only a week after Buckingham Palace had said the trip to the Vatican would go ahead despite the pontiff’s continued illness.

The royal visit to the Vatican and Italy from April 7-10 was to celebrate the papal jubilee and the relationship between the Catholic Church and the Church of England.

-with AAP