Pope Francis remains on daily oxygen therapy during his third week in the hospital, with his prognosis still "guarded," the Holy See Press Office said in a Saturday update. Francis has been critically ill with double pneumonia and chronic bronchitis after being admitted to Rome's Gemelli Hospital on February 14.

Pope Francis followed the Vatican’s weeklong spiritual retreat via videoconference on Monday as he continued his recovery from double pneumonia and looked ahead to the 12th anniversary of his election amid questions about what the future of his papacy might look like.

Pope Francis increased his physical therapy with his condition remaining stable on Wednesday, marking the start of Lent by receiving ashes on his forehead and calling the parish priest in Gaza, the Vatican said.

Pope Francis' health has improved, Vatican sources indicated to CBS News on Friday, saying he was not currently in critical condition after exactly two weeks in hospital for bronchitis that developed into pneumonia in both lungs.

In his prepared March 9 homily for the first Sunday of Lent, the Holy Father said difficulties and trials do not "end in failure” for Christians who embrace their relationship with God our redeemer.