Juan Guaidó, Venezuela's most powerful opposition leader, has declared that he has met with armed forces and is starting the "final phase" to oust President Nicolás Maduro.

Early Tuesday morning, Guaidó released a three-minute video describing the Venezuelan people's fight. He was flanked by men with helmets and weapons as he discussed ending the "usurpation," a term he has often used to describe Maduro's hold on the once-oil rich nation. Guaidó, 35, stood near opposition leader Leopold López, who has previously been under house arrest.

Reports have emerged of a confrontation at an air base in Caracas where Guaidó is believed to have recorded the video. Reuters reported that one of its journalists saw security forces fire tear gas at Guaidó and dozens of men in military uniform.

Guaidó leads Venezuela's National Assembly and has been recognized as the country's interim president by the United States and dozens of other nations.

Lawmakers in Washington have already begun showing their support, with Sen. Marco Rubio (R-Fla.) tweeting, "This is the moment for those military officers in #Venezuela to fulfill their constitutional oath & defend the legitimate interim President."

Rubio posted a video of a "showdown" on a highway. He said Maduro called for armed groups to go to the streets; the senator also said Chinese technicians have helped the Maduro regime take down social media communications.

"The U.S. Government fully supports the Venezuelan people in their quest for freedom and democracy. Democracy cannot be defeated," Secretary of State Mike Pompeo said via Twitter, welcoming the start of "Operación Libertad."

President Trump has been briefed on the developments, White House spokesperson Sarah Sanders told reporters.

This is a developing story. Details may change as more information becomes available.

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