Pope Francis leads the Angelus prayer at St Peter's square on March 17, 2013 at the Vatican. Pope Francis begins his papacy in earnest today ahead of his formal inauguration mass, with a weekly prayer address used by previous pontiffs to comment on international affairs. The pope's first Angelus prayer, delivered from a window high above St Peter's Square, is a chance for the first Latin American pontiff to begin to sketch out a more global vision for the role of the Roman Catholic Church. AFP PHOTO / GABRIEL BOUYS