Updated

The Vatican is hosting Nobel laureates, U.N. and NATO officials and a handful of nuclear powers at a conference aimed at galvanizing support for a global shift from the Cold War era policy of nuclear deterrence to one of total nuclear disarmament.

Pope Francis is due to address the conference Friday, adding his voice to the campaign that produced a new U.N. treaty calling for the elimination of atomic weapons, and a Nobel Peace Prize for the small advocacy group that was instrumental in pushing the treaty through.

Among those speaking at the two-day meeting are Beatrice Fihn, executive director of the Nobel-winning International Campaign to Abolish Nuclear Weapons, and Masako Wada, who survived the atomic bombing of Nagasaki and has gone onto become a prominent disarmament activist.