The Vatican described his condition as critical for the first time on Saturday, reporting that the 88-year-old Francis needed supplemental oxygen and blood transfusions after a "prolonged asthma-like respiratory crisis.

The announcement on Saturday evening indicated that Francis’ medical condition had become more complicated since an update from his doctors on Friday.

Pope Francis, battling double pneumonia, remains in a critical condition and his prognosis is still guarded because of the "complexity" of his clinical condition, the Vatican said on Sunday. The pope was admitted to Rome's Gemelli hospital on February 14 after having trouble breathing for several days and subsequently had pneumonia diagnosed in both lungs.