In a video statement posted on social media Tuesday night, Guaidó also urged the military to join with those clamoring for change in Venezuela.
The man recognized by more than 50 nations as Venezuela's rightful leader said the country's disputed president, Nicolas Maduro, "doesn't have the backing or the respect" of the military.
Guaidó said he called for the uprising to restore Venezuela’s constitutional order, broken when Maduro was sworn in earlier this year for a second term following elections boycotted by the opposition and considered illegitimate by dozens of countries.
Guaidó called for a military uprising earlier Tuesday, a rebellion dubbed “Operation Freedom,” thus issuing the most serious challenge yet to Maduro's contested rule.
Amid the confusion, Maduro tried to project an image of strength, saying he had spoken to several regional military commanders who reaffirmed their loyalty.
“Nerves of steel!” he said in a message posted on Twitter.
Maduro said the Guaidó mutiny had been defeated and Venezuela would never surrender to “imperialist forces,” as The Guardian noted.
Protesters erected barricades of debris at several downtown intersections about 10 blocks from the presidential palace, but police in riot gear moved in quickly to clear the roads. Most shops and businesses were closed and the streets of the capital unusually quiet, as people huddled at home to await the outcome of the day’s drama.
In one dramatic incident during a chaotic day of violent street battles for a crowd that quickly swelled to a few thousand, several armored vehicles plowed into a group of anti-government demonstrators trying to storm the capital’s air base, hitting at least two protesters.
Guaidó’s call for a military uprising drew quick support from the Trump administration and fierce resistance from forces loyal to the embattled Maduro.
The Associated Press contributed to this report.