A group of nuns, priests and students from a Catholic university gathered outside the Gemelli Hospital in Rome on Monday to pray for Pope Francis who is battling pneumonia. (AP Video: Florent Bajrami)

As Pope Francis continued his treatment at Rome’s Gemelli hospital Sunday, he expressed gratitude to medical staff while marking the approaching third anniversary of Russia’s invasion of Ukraine in a prepared Angelus message.

Rome's Gemelli University Hospital, located just five kilometres from the Vatican, has long been the preferred medical facility for popes. Situated on Monte Mario in the western part of the Italian capital,