Canadian Prime Minister Justin Trudeau (C) attends the opening ceremony of 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 / Mark SchiefelbeinMARK SCHIEFELBEIN/AFP/Getty Images

Britain's Prime Minister Theresa May (C) 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

Britain's Prime Minister Theresa May (C) 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

India's Prime Minister Narendra Modi attends the opening ceremony of 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 / Mark SchiefelbeinMARK SCHIEFELBEIN/AFP/Getty Images

Chinese President Xi Jinping is seen on screens as he makes a speech during the opening ceremony of 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 / NICOLAS ASFOURINICOLAS ASFOURI/AFP/Getty Images

European Council President Donald Tusk (L) and European Commission President Jean-Claude Juncker (R) attend the opening ceremony of 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 / Mark SchiefelbeinMARK SCHIEFELBEIN/AFP/Getty Images

Members of the media try to take pictures of US Secretary of State John Kerry (not pictured) 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 / STEPHANE DE SAKUTINSTEPHANE DE SAKUTIN/AFP/Getty Images

A televison crew gets ready to report from 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 / STEPHANE DE SAKUTINSTEPHANE DE SAKUTIN/AFP/Getty Images