(FILES) In this file picture taken on July 29, 2017 Venezuelan nationals protest against Venezuelan President Nicolas Maduro and the Constituent Assembly in Cucuta, Norte de Santander Department, Colombia. Colombia holds the first round of the presidential election on May 27, 2018 with a great challenge awaiting the new government in the border with Venezuela and Ecuador where drug trafficking, social prostration and migration grow in numbers and despair. / AFP PHOTO / Schneyder Mendoza