Francis is being treated with supplemental oxygen to assist him with breathing, the Vatican said Tuesday, a day after he suffered two episodes of acute respiratory failure.

Pope Francis suffered two episodes of "acute respiratory insufficiency" on Monday, the Vatican said, a setback for the 88-year-old pontiff as he battles double pneumonia. Francis, who has been in Rome's Gemelli Hospital since February 14, is again receiving "non-invasive, mechanical ventilation" to help with his breathing.