Pope Francis, 88, is receiving treatment for a “complex clinical situation” and will remain in Rome’s Gemelli hospital for as long as necessary, the Vatican announced on Monday.

The pontiff was admitted on Friday for medical tests and treatment following several days of bronchitis symptoms. However, an update from Vatican spokesman Matteo Bruni revealed that he has developed a polymicrobial infection affecting his respiratory tract, leading to an adjustment in his treatment plan.

Despite his condition, Bruni assured reporters that the Pope remains in good spirits. A Vatican statement confirmed that his condition is being closely monitored, adding:

“All tests carried out to date are indicative of a complex clinical picture that will require appropriate hospitalisation.”

As a result of his illness, the Pope’s weekly general audience scheduled for Wednesday has been canceled. Over the weekend, the Vatican had reported that the Pope was in a stable condition, with doctors recommending complete rest to aid his recovery.

Pope Francis was unable to deliver his usual Sunday prayer in St. Peter’s Square or preside over a special mass for artists in honor of the Catholic Church’s Jubilee Year.

A further update on his condition is expected later on Monday as the world watches and prays for his swift recovery.