ISTANBUL, TURKEY - DECEMBER 01: People walk past a branch of Turkish bank VakifBank on December 1, 2017 in Istanbul, Turkey. The trial of Mr. Reza Zarrab, an Iranian-Turk who ran a foreign exchange and gold dealership continues in New York. In recent days testimony Mr. Zarrab implicated a number of Turkish Banks as well as high ranking government officials. Mr. Zarrab is accused of managing a billion-dollar scheme to smuggle gold for Iranian oil and conspiring to violate United States sanctions against Iran. (Photo by Chris McGrath/Getty Images)