Tens of thousands of people have been marching in the Venezuelan capital, Caracas, in support of a referendum to force President Hugo Chavez out of office.
The march is the first large opposition protest in months
Earlier in the day, opposition groups delivered a petition to the electoral authorities - signed by more than 2.5 million people - to demand the early vote.
Venezuela's constitution states that a referendum may be held halfway through a president's term of office - a date which Mr Chavez reached on Tuesday.
Mr Chavez's opponents say they have delivered well over the minimum signatures required - 20% of the registered electorate - to force the poll.
One of the opposition leaders, Timoteo Zambrano, told the BBC that now the government did not have the authority to reject the referendum.
"The signatures are safe where they should be so that the referendum process can get going once and for all," another opposition leader, Enrique Mendoza, was quoted as saying by Reuters news agency.
The signatures will now have to be checked by a new National Electoral Council whose members are due to be named by Venezuela's Supreme Court at the weekend.
The march is the first large opposition protest since a two-month general strike earlier this year failed to oust President Chavez.
Chavez is accused of ruining Venezuela's economy
The demonstrators - who have been streaming to Libertador Avenue in the heart of Caracas from six different points - chanted "Chavez out" and "Chicken - what are you doing in Argentina?", referring to Mr Chavez's ongoing visit to Buenos Aires.
"I can't express my happiness," 70-year-old marcher Maria Cristina de Paris said.
"We did it. We won, " she added.
Opposition leaders claimed that about one million people came to support the referendum request.
President Chavez, who was elected on promises to bring about economic prosperity in the world's fifth largest oil exporter country, has been accused of mismanaging the economy.
The opposition also says Mr Chavez has become increasingly authoritarian and is dragging Venezuela toward Cuba-style communism.
But the president - who commands strong support among the country's poor - says a political elite is pushing for his removal to regain the privileges it lost when he took power.
He also insists that the signatures are fake, and "don't meet constitutional requirements".
Mr Chavez's supporters have also said they will stage a rally to back the embattled president.