U.S. Vice President Joe Biden gestures during a news conference at the Swedish government offices, Rosenbad in Stockholm, Sweden, August 25, 2016. REUTERS/Anders Wiklund/TT News Agency

Former U.S. President Bill Clinton takes the stage as his daughter Chelsea Clinton embraces during the closing session of the Clinton Global Initiative 2016 (CGI) in New York, U.S., September 21, 2016. REUTERS/Shannon Stapleton

Former U.S. President Bill Clinton puts his hand over his heart after the closing of the Clinton Global Initiative 2016 (CGI) in New York, U.S., September 21, 2016. REUTERS/Shannon Stapleton

Colombian President Juan Manuel Santos speaks during a Reuters Newsmaker conversation in Manhattan, New York, U.S., September 21, 2016. REUTERS/Andrew Kelly

Venezuela's President Nicolas Maduro speaks during his weekly broadcast "En contacto con Maduro" (In contact with Maduro) in Caracas, Venezuela September 20, 2016. Miraflores Palace/Handout via REUTERS

A car is filled with gasoline at a gas station pump in Carlsbad, California August 4, 2015. REUTERS/Mike Blake

United States one dollar bills are seen on a light table at the Bureau of Engraving and Printing in Washington November 14, 2014. REUTERS/Gary Cameron/File Photo

Container vessel Hanjin Rome sits in the eastern anchorage area in Singapore September 9, 2016. REUTERS/Edgar Su/File Photo