U.S. President Barack Obama (L) and Prime Minister of Australia Tony Abbott chat before the start of the "Welcome to Country" ceremony at the G20 summit in Brisbane November 15, 2014. The meeting of leaders of the Group of 20 economies has opened in Brisbane with Abbott stressing the importance of global economic issues at a summit that has been dominated by the crisis in Ukraine, climate change and the United States's Asia-Pacific pivot. REUTERS/Mark Baker/Pool (AUSTRALIA - Tags: POLITICS BUSINESS)