epa05026688 US president Barack Obama (C) chats Canadian Prime Minister Justin Trudeau (L) prior to family photo session during G20 summit in Antalya, Turkey, 15 November 2015. In additional to discussions on the global economy, the G20 grouping of leading nations is set to focus on Syria during its summit this weekend, including the refugee crisis and the threat of terrorism. EPA/TOLGA BOZOGLU