Pope Leo XIV made his first public appearance to those gathered at St. Peter's Square in the Vatican on Sunday after cancer surgery.

Oct. 18 (UPI) -- Pope Leo XIV made his first public appearance to those gathered at St. Peter's Square in the Vatican on Sunday, thanking them for their well wishes and promising to return gradually to his duties after having surgery last week to remove part of a cancerous lung.

He addressed the thousands gathered in the square from a window of the Apostolic Palace, leading the Angelus prayer. The appearance came one day after doctors released him from Rome's Agostino Gemelli Hospital.

"I have truly felt your support. Thank you," the pontiff said.

"Now that this delicate phase is behind me, I will gradually resume my activities, always with God's help and your prayers."

Pope Leo, 71, underwent surgery Tuesday to remove a nodule detected in his right lung. During the operation, doctors determined the pope had adenocarcinoma, the most common type of lung cancer, and removed the lower lobe of his lung.

The pope said his hospitalization "has made me feel especially close to those facing illness and infirmity."