Pope Francis is responding ''well'' to therapy for double pneumonia and has shown a ''gradual, slight improvement'' in recent days, the Vatican said Saturday. But as a precaution his doctors have decided to keep his prognosis as guarded.

Pope Francis, who has been in hospital for almost three weeks battling double pneumonia, is in stable condition and is doing some physical therapy, the Vatican said on Thursday. The 88-year-old pontiff was admitted to Rome's Gemelli hospital on February 14 with a severe respiratory infection that has required continuously evolving treatment.

The Vatican said Pope Francis is showing "gradual, slight improvement." The 88-year-old has been in the hospital for 23 days, battling double pneumonia.

Pope Francis is responding well to treatment for pneumonia after three weeks in hospital, the Vatican said Saturday, adding that the 88-year-old was showing "a gradual, slight improvement".