Tens of thousands of people gathered on Sunday at the famous Copacabana beach in Rio, Brazil, calling for the impeachment of President Dilma Rousseff.
Many voters have accused the president of failing to deal with corruption, blaming her for the economy's worst slump in 25 years, while recent polls show that support for Rousseff has fallen deeply.
Protesters also demonstrated outside congress in the capital Brasilia.
Many wore the yellow shirts of the Brazilian football team, singing the national anthem, carrying banners saying "Dilma Out".
Police said about 137,000 people took part in the demonstrations in Sao Paulo.
"We want things to change and if the people don't go in the street that's impossible," a retired engineer Elino Alves de Moraes, said.
There have also been demonstrations where protesters showed their support for the president, many claiming calls for her to step down as a coup attempt.
Brazilian President Dilma Rousseff said on Wednesday that she has never considered quitting from her post as the political crisis has been eroding her popular ratings since the last year’s Petrobras investigation.
Speaking to Brazilian TV channel Sistema Brasileiro de Televisão (SPT) on Wednesday, Rousseff said that the recent political crises regarding the Petrobras scandal and impeachments on her government in the Congress would never hinder her efforts to revive Brazil’s flagging economy.
As the economy gradually stagnated, Rousseff’s policies came under criticism by her opponents who have impeached her for allegedly distorting fiscal stability by allowing her government to spend more in the run-up to her re-election in October last year.
The president of Brazil's Senate Renan Calheiros warned the Congress on Monday on impeachment attempts that aimed at removal of Rousseff from the post would "set the country on fire."