Pope Francis, who is being treated in hospital for double pneumonia, will not appear in public on Sunday to lead his usual prayer with pilgrims for a second consecutive week, the Vatican said.

The Vatican said Pope Francis has the "onset of bilateral pneumonia," and that tests, a chest X-ray and the pope's clinical condition present a "complex picture."

The Vatican said that the pontiff had pneumonia in both lungs and that he “continued to present a complex picture.”