"Now is the time to act in support of democracy, and respond to the needs of the desperate Venezuelan people. The United States will take action against and hold accountable those who oppose the peaceful restoration of democracy in Venezuela", Pompeo said in a press release issued late on 23 February.
The secretary of state also thanked Colombia and Brazil for their efforts to provide humanitarian assistance to Venezuela.
Russia, as well as China and several other countries, has endorsed Maduro as the country's legitimate president, and warned that unauthorised deliveries of aid to Venezuela would be a provocation saying they could lead to clashes between supporters and opponents of the move that could subsequently be used as a pretext for military action against Caracas.
The situation in crisis-torn Venezuela escalated in January, when opposition leader Juan Guaido proclaimed himself interim president, disputing last year's re-election of Maduro. Guaido was almost instantly recognised by the United States and some other countries, including Colombia.