Pope Francis is in hospital in Rome after scheduled surgery on his large intestine.

The news of the surgery came from the Vatican just three hours after Francis had cheerfully greeted the public in St Peter’s Square and told them he will go to Hungary and Slovakia in September.

It is the pope’s first known hospitalisation since he was elected to the papacy in 2013.

In a statement late on Sunday (local time), Holy See spokesman Matteo Bruni said 84-year-old Francis had general anaesthesia during the surgery necessitated by a stenosis, or narrowing, of part of the large intestine.

The surgery was performed by Doctor Sergio Alfieri, director of the digestive surgery department at Rome’s Gemelli Polyclinic.

The Vatican did not say how long the surgery lasted.

Earlier, it said Francis had been diagnosed with “symptomatic diverticular stenosis of the colon.

A week ago, Francis used his same Sunday appearance to ask the public for special prayers for himself, which may have been related to the planned surgery.

“I ask you to pray for the pope, pray in a special way,” he asked the faithful in the square on June 27.

“The pope needs your prayers,” he said, adding his thanks and saying “I know you will do that”.

Francis is in generally good health, but he did have part of one lung removed as a young man. He also suffers from sciatica, in which a nerve affects the lower back and leg, a painful condition that has forced him at times to skip scheduled appearances.

A 10th-floor papal suite is kept available at the hospital in case of need.

While Church law provides for a prelate to take over the administration of the Roman Catholic Church if a pope dies, there is no known provision for a delegation of powers if a pope is temporarily incapacitated.

The pope had a particularly demanding set of appointments last week, including celebrating a Mass on Tuesday to mark the Catholic feast day honouring Saints Peter and Paul, and later in the week, presiding at a special prayer service for Lebanon.

On June 28, he also had a long private audience at the Vatican with US Secretary of State Antony Blinken. Throughout all those engagements, Francis appeared to be in good spirits.

Usually, besides the traditional Sunday noon blessing and remarks from a window of the Apostolic Palace overlooking St Peter’s Square, the pontiff holds a public audience every Wednesday. But, in deference to Rome’s heat, the Wednesday appointment gets suspended during July.

Gemelli doctors have performed surgery before on popes, notably Pope John Paul II, who had what the Vatican said was a benign tumour in his colon removed in 1992. John Paul had several other surgeries at the hospital, including after being shot by a gunman in St Peter’s Square in 1981.

John Paul also had several medical issues in his final years, including severe complications from Parkinson’s disease, and had numerous stays at Gemelli.