Pope Francis is suffering from a respiratory infection and will stay in the hospital for treatment for several days, the Vatican says.
The head of the Catholic Church had been taken to Rome's Gemelli University Hospital on Wednesday afternoon.
Vatican spokesman Matteo Bruni said the 86-year-old pontiff had complained of breathing problems in recent days.
At the hospital, tests revealed the infection.
Tests indicated the Pope does not have COVID-19, Bruni said.
On Wednesday morning, the pontiff held his weekly general audience in front of thousands of believers in St Peter's Square.
In July 2021, the Pope previously had intestinal surgery at the same hospital and spent 11 days there recovering.
In a recent interview, he indicated that he was again having trouble with his intestines.
The Pope has also been suffering from severe knee problems for more than a year, which often require him to use a wheelchair.
Francis has so far declined to undergo surgery on his knee - reportedly in part because he did not react well to anaesthesia during the previous operation.
© DPA 2023