MOSCOW (Sputnik) - US Secretary of State Mike Pompeo has warned that the United States will hold everyone who tries to hamper efforts to "restore" democracy in Venezuela accountable, commenting on the US-backed Venezuelan opposition's failed attempt to ensure the delivery of unauthorised humanitarian aid to the country from Colombia and Brazil.

"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.

Attempts to bring unauthorised aid into Venezuela have led to clashes between Venezuelan police officers, trying to prevent aid-filled trucks from crossing into the country without permission and protesters, prompting Caracas to sever diplomatic and political relations with Bogota.

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.

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Venezuelan President Nicolas Maduro has refused to allow in the US aid deliveries, blasting them as a ploy to topple his government. The government first closed the land border with Brazil, the sea border with the Lesser Antilles, and then shut several border crossings with Colombia.

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.