CARACAS - Venezuelan opposition leader Juan Guaido on Saturday called on supporters to lead a new wave of protests against President Nicolas Maduro, who has held on to power despite an economic crisis and aggressive U.S. sanctions.

Guaido won broad international backing in January after declaring Maduro's 2018 re-election a fraud and assuming a rival interim presidency. But momentum since then has waned as repeated efforts to force him from office have failed.

Speaking at a rally in Caracas meant to usher in a new phase of activism, Guaido said the opposition should stage frequent protests to boost pressure on the deeply unpopular Maduro. "Every Venezuelan has the obligation to carry on the fight, to go into the streets to demand their rights," Guaido said at rally in eastern Caracas before cheering demonstrators who waved Venezuela's red, yellow, and blue flag and waved signs denouncing Maduro as a dictator.

"Today we have to continue advancing the protests until we obtain the freedom of all Venezuela."

In the coming days, groups including students, teachers and nurses plan to hold protests, he said.

Demonstrations have in the past galvanized the opposition and left the ruling Socialist Party isolated.

But the economic crisis has made day-to-day existence an enormous struggle, leaving many weary and apathetic. And change in Venezuela will also hinge on a shift in allegiance of the armed forces, which remain loyal to Maduro.

That remains the crucial difference between Venezuela and Bolivia, where a combination of street protests and military pressure led President Evo to resign following criticism that his October re-election was the result of fraud.

"I know there's a small chance Guiado will get Maduro out," said Rosmely Guerra, 49, a sociology professor. "But even if there's just a 1% chance, I'm going to throw 99% of my faith behind it. What other option do we have?"

The Socialist Party held a rally in downtown Caracas in support of Bolivia's Morales.

"We're here because we want to make it clear that if someone meddles with our country, it won't be the same as in Bolivia," said Aida Romero, 66, who works in a government food program. "We're willing to do anything. This revolution is peaceful, but it's also armed."

Venezuela's collapsing economy has spurred an exodus of more than 4 million seeking better access to food and medicine.

More than 50 countries have recognized Guaido as Venezuela's legitimate president and the United States has implemented a sanctions program that has crippled Venezuela's oil exports. Maduro dismisses Guaido as a puppet of the United States, and blames the economic problems on U.S. sanctions.