Senegal's President Macky Sall arrives for the G20 Summit at the International Expo Center in Hangzhou on September 4, 2016. G20 leaders confront a sluggish global economy and the winds of populism as they open annual talks, but the long war in Syria and the South China Sea territorial dispute hang over the summit. / AFP PHOTO / POOL / Rolex DELA PENAROLEX DELA PENA/AFP/Getty Images

Kazakhstan's President Nursultan Nazarbayev arrives for the G20 Summit at the International Expo Center in Hangzhou on September 4, 2016. G20 leaders confront a sluggish global economy and the winds of populism as they open annual talks, but the long war in Syria and the South China Sea territorial dispute hang over the summit. / AFP PHOTO / POOL / Rolex DELA PENAROLEX DELA PENA/AFP/Getty Images

Laos' President Bounnhang Vorachith arrives for the G20 Summit at the International Expo Center in Hangzhou on September 4, 2016. G20 leaders confront a sluggish global economy and the winds of populism as they open annual talks, but the long war in Syria and the South China Sea territorial dispute hang over the summit. / AFP PHOTO / POOL / Rolex DELA PENAROLEX DELA PENA/AFP/Getty Images

South Korea's President Park Geun-Hye arrives for the G20 Summit at the International Expo Center in Hangzhou on September 4, 2016. G20 leaders confront a sluggish global economy and the winds of populism as they open annual talks, but the long war in Syria and the South China Sea territorial dispute hang over the summit. / AFP PHOTO / POOL / Rolex DELA PENAROLEX DELA PENA/AFP/Getty Images

South Africa's President Jacob Zuma arrives for the G20 Summit at the International Expo Center in Hangzhou on September 4, 2016. G20 leaders confront a sluggish global economy and the winds of populism as they open annual talks, but the long war in Syria and the South China Sea territorial dispute hang over the summit. / AFP PHOTO / POOL / Rolex DELA PENAROLEX DELA PENA/AFP/Getty Images

Laos' President Bounnhang Vorachith (C) arrives at the G20 Summit at the International Expo Center in Hangzhou on September 4, 2016. G20 leaders confront a sluggish global economy and the winds of populism as they open annual talks, but the long war in Syria and the South China Sea territorial dispute hang over the summit. / AFP PHOTO / POOL / Etienne OliveauETIENNE OLIVEAU/AFP/Getty Images

(Front L to R) China's President Xi Jinping, Russia's President Vladimir Putin, President of the European Commission Jean-Claude Juncker, Kazakhstan's President Nursultan Nazarbayev walk across the ground for a group picture prior to a dinner banquet at the G20 Summit in Hangzhou on September 4, 2016. G20 leaders confront a sluggish global economy and the winds of populism as they open annual talks, but the long war in Syria and the South China Sea territorial dispute hang over the summit. / AFP PHOTO / Johannes EISELEJOHANNES EISELE/AFP/Getty Images

Laos' President Bounnhang Vorachith arrives for the G20 Summit at the International Expo Center in Hangzhou on September 4, 2016. G20 leaders confront a sluggish global economy and the winds of populism as they open annual talks, but the long war in Syria and the South China Sea territorial dispute hang over the summit. / AFP PHOTO / POOL / Rolex DELA PENAROLEX DELA PENA/AFP/Getty Images