Venezuela's opposition-dominated National Assembly on Tuesday ratified Juan Guaido as the country's interim president until new elections can be held.
The endorsement came a day after the government of President Nicolas Maduro said its lawmakers would return to the legislature, which they abandoned three years ago.
The vote represented "unrestricted political support for the leadership of Juan Guaido as president of the National Assembly and as president in charge... until the cessation of usurpation occurs," according to a statement from the National Assembly.
The decision implies that US-backed Guaido, recognized as interim president by more than 50 countries, will continue to head the legislature after January 5 when his term ends.
The United States welcomed the move, saying it reflected "the unity and strength of the democratic opposition."
Deputies from the ruling socialist party walked out of the National Assembly in 2016 after losing control in elections, and the government set up its own body, the Constituent Assembly, to sideline the opposition-dominated body.
On Monday, Maduro's government said its deputies would return to the National Assembly "in the interest of deepening and extending the dialogue" with the opposition.
That announcement came hours after Guaido announced that talks aimed at resolving the country's long-running political had ended.
Maduro called off the talks, which were initially held in Oslo and then moved to Barbados, on August 7 in response to US sanctions against his government.
"After more than 40 days during which he refused to continue, we can confirm that the Barbados (dialogue) mechanism has ended," Guaido said.
Guaido earlier this year declared himself interim president with the backing of the United States and other western powers, saying elections that returned Maduro to power had been undermined by fraud.
The presidency of the National Assembly normally rotates annually under an agreement within the opposition coalition.
The position would next fall to minority movements within the opposition, including parties who have signed a pact with Maduro paving the way for a return of his socialist party to the legislature.