The 88-year-old pontiff is now able to spend some time during the day off high flows of oxygen and use just ordinary supplemental oxygen delivered by a nasal tube, the Holy See press office said. Doctors are also trying to cut back on the amount of time he uses a noninvasive mechanical ventilation mask at night, to force his lungs to work more.

The Vatican press office released a photo of Pope Francis on Sunday in a private chapel of Rome's Gemelli Hospital.

Francis' condition has recently improved despite some complications, with the pope saying he no longer feels in imminent danger.