HOUSTON (Reuters) – The United States in January imposed sanctions on Venezuela’s most important global business – producing and selling crude oil – as the Trump administration ratcheted up its bid to force socialist president Nicolas Maduro out of power.

FILE PHOTO: The Suezmax sized oil tanker Karvounis lies at anchor stranded off the coast of Louisiana for lack of a bank letter of credit to discharge its cargo of Venezuelan heavy crude, south of Port Fourchon, Louisiana, U.S. August 17, 2017. REUTERS/Jonathan Bachman

Venezuela’s oil exports – accounting for more than 95 percent of the country’s export revenue – have dropped by some 40 percent since January. At the same time, it has been unable to import all the fuel it needs for blending with