Brazil's Congress has received a request from President Dilma Rousseff to hold a referendum on political reform in response to the worst social unrest in 20 years.
The move, widely supported by the public, came after three weeks of protests over corruption and public spending which marred the Confederations Cup, a dress rehearsal for next year's football World Cup, which will also be held in Brazil.
The nightly rage that made headlines around the world has waned somewhat, but no one rules it flaring up again like it did after the Cup, when a million people took to the streets.
On Tuesday night truck drivers blocked roads in at least 10 states to press for the elimination of tolls and fuel subsidies.
The proposal for a plebiscite was delivered to senate and congressional president Renan Calheiros by Justice Minister Jose Eduardo Cardozo and vice president, Michel Temer, state news service Senado said.
"Calheiros announced he would act so that any changes resulting from the referendum take effect from (October) 2014," a year before presidential elections are to be held, Senado said.
Cardozo said the referendum will include the reform of election campaign financing, the congressional voting system, rules governing coalitions and legislation on secret ballots.
"The executive is merely making a simple suggestion," Temer told reporters. "It is congress which will oversee (the process) from the start through to the conclusion."
The protests began in Sao Paulo and Rio de Janeiro over hikes in public transport fares but mushroomed into demands for improvements in crumbling public services and for an end to rampant corruption.
Some 1.5 million Brazilians took part in the protests at their height.
Leftist leader Rousseff last week proposed a national pact with state governors to boost public services and guarantee a balanced budget.
A Datafolha poll showed that 68 percent of Brazilians back Rousseff's proposals.
But that is no guarantee for its approval, and even less so in the swift timeframe sought by the president. She wants the reforms in place by October, the deadline for them to be applied in the general elections of October 5 of next year.
The ruling Workers Party has been seeking political reform for years, and there has been debate in the legislature albeit in vain.
The opposition is opposed to holding a referendum. It says Congress can approve changes by itself and that aiming for 2014 is too fast. It also says Rousseff should have contacted the opposition to discuss her plans.
Congress reserves the right to call a referendum and to implement any resulting political reforms.
Rousseff has a majority in the legislature but some sections of that broad support are not always loyal, especially since her approval rating has dropped 27 points because of the street protests.
The drop is also affecting mayors, governors, both allies and enemies of the president.
"When a ship looks like it is sinking, the rats are the first to jump off," said Carlos Lupi, former leader of the Rousseff-allied Labor Party, indicating friends could start dumping the president.
Two major newspapers, including O Globo in Rio, criticized the president's plans as too vague and said the government should take more concrete action like streamlining the country's 39 ministries.
The electoral commission needs at least 70 days to convene a referendum, making September 8 the earliest possible date.