The announcement of additional aid comes as the Trump administration on Friday added Venezuela's oil boss and key intelligence officers to a long list of Maduro loyalists under U.S. financial sanctions.
The 250 tons of food supplies, hygiene kits and nutritional supplements will begin arriving Saturday to the border city of Cucuta, where tons of boxes of emergency aid stamped with the U.S. flag are already warehoused awaiting delivery into Venezuela.
The email sent Friday was provided to The Associated Press by a congressional aide who wasn't authorized to discuss the matter publicly.
The aid came at the request of opposition leader Juan Guaido, who the U.S. and dozens of other countries have recognized as Venezuela's rightful leader after President Nicolas Maduro last month was sworn in for a second term widely seen as illegitimate.
Guaido has vowed to deliver the aid over the objections of Maduro, who in an exclusive interview Thursday with the AP said that the offer of U.S. assistance represents mere "crumbs" compared to hostile efforts to block the country's oil exports and restrict its access to foreign funding.
While the U.S. military has long supported civilian-led humanitarian assistance missions around the world, this is the first time they are being used to deploy aid for Venezuela. Last year, the U.S. government sent more than $100 million in aid to Cucuta to help Colombian authorities absorb some of the estimated 3 million of Venezuelans fleeing hyperinflation and food shortages.
In slapping new sanctions on Maj. Gen. Manuel Quevedo, the president of the Venezuelan state oil company PDVSA, U.S. Treasury Secretary Steven Mnuchin said the oil executive had been instrumental in propping up what he called Maduro's illegitimate regime.
In the AP interview Maduro said Quevedo had been in India this week looking to drum up new business for PDVSA after the company was itself hit with sanctions aimed at cutting off an estimated $11 billion in profits.
The new sanctions also target four high-ranking intelligence officials, including the head of the feared SEBIN intelligence police and an elite commando unit known as FAES that is accused of several targeted killings.
In a statement, Mnuchin accused the officials of corruption and helping Maduro repress democracy in Venezuela — which includes using "torture and other brutal use of force."
"We are intent on going after those facilitating Maduro's corruption and predation," Mnuchin said, adding that Quevedo and others have syphoned off funds that "rightfully belong to the people of Venezuela."
The U.S. sanctions block access to any property the individuals own in the United States and bans U.S. citizens from doing business with them.
As U.S. pressure mounts, Secretary of State Mike Pompeo told reporters Friday in Reykjavik, Iceland, that he sees clear signs that Maduro is starting to understand Venezuelans reject him as their leader.
In the AP interview, Maduro said he was willing to meet President Donald Trump at any time or place to resolve the crisis over U.S. recognition of Guaido.
Pompeo said Maduro's request wasn't new, but it reflects that he's realizing his crisis-riddled nation rejects his "model of governance."
Pompeo wouldn't say whether he would send envoy Elliott Abrams to meet Maduro in Caracas.
Maduro told the AP that his foreign minister has met Abrams twice recently in New York for secret talks.
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