Pope Francis continues to improve from double pneumonia, the Vatican has said, though doctors said he needs more days of “clinical stability” before they revise their guarded prognosis.

The 88-year-old was able to begin alternating high-flow supplemental oxygen, delivered by a nasal tube, with a mask in a sign of his improved respiratory condition, the Vatican said in a late update.

Candles and flowers for Pope Francis (Andrew Medichini/AP)

For the second day in a row, doctors did not say Francis was in critical condition.

But they said that given the complexity of his lung infection, “further days of clinical stability are needed” before they declare he is out of danger.

Francis has been in Rome’s Gemelli hospital since February 14.