Pope Francis reached the two-week mark recovery from pneumonia Friday as doctors suggested he had overcome the most critical phase of the infection while holding out on declaring him out of danger entirely.

The Vatican reported Friday that he experienced sudden breathing problems that required “non-invasive mechanical ventilation” but that he remained “alert.”

Pope Francis, who has been hospitalised for two weeks battling double pneumonia, has spent another peaceful night and is now resting, the Vatican said on Friday. Francis, 88, was admitted to Rome's Gemelli hospital on February 14 with what was originally described as a bronchitis and was later revealed to have developed into something more serious.

The pope suffered an "isolated attack of bronchospasm" which caused vomiting with inhalation, the Vatican said on Friday.

The Pope is receiving gas to help him breathe and is said to be in "good spirits" following the latest crisis.