In his first "Urbi et Orbi" (to the city and the world) message, Francis also called for peace between Israelis and Palestinians, an end to the civil war in Syria, and political solutions to conflicts in several African countries.
The former Cardinal Jorge Bergoglio of Argentina also condemned the "iniquitous exploitation of natural resources" and urged everyone to be "guardians" of creation.
More top news
Seventy seven people have been charged after a major investigation by Police Scotland recovered more than 30 million indecent images.
Whitehall's latest re-homed feline has got involved in a political scrap between Downing Street's Larry and the Foreign Office's Palmerston.
Daniel Rodriguez, also known as Grymey D, used Instagram, Facebook and Blackberry Messenger to contact girls who he invited to his home.