A man walks past boxes of USAID humanitarian aid at a warehouse at the Tienditas International Bridge on the outskirts of Cucuta, Colombia, Feb. 21, 2019, on the border with Venezuela. Venezuela's President Nicolas Maduro said he’s weighing whether to shut down the border with Colombia, where the bulk of aid meant for Venezuela is being stockpiled and exiled leaders have been gathering ahead of a fundraising concert Friday. (AP Photo/Fernando Vergara)