Brazilian prosecutors on Thursday lodged corruption charges against the speaker of the lower house -- a key figure in the country's current political crisis -- and also against a former president.

Eduardo Cunha, speaker of the Chamber of Deputies, was alleged to have taken at least $5 million in bribes as part of a sprawling corruption network centered on state oil company Petrobras.

Prosecutor General Rodrigo Janot alleged that Cunha received payoffs relating to contracts to build two survey vessels for Petrobras.

Fernando Collor de Mello, a former president who left office in 1992 in another corruption scandal before returning to politics as a senator, was also charged in connection with the Petrobras scheme.
The Supreme Court, which will consider the politicians' cases, confirmed that charges had been filed against Collor. But no details were provided.

The probe into the embezzlement and bribes network at Petrobras, dubbed Operation Car Wash, has netted a Who's Who of Brazil's elite, but Cunha and Collor are among the highest profile.

Cunha has risen to prominence as a key player in threats to impeach embattled leftist President Dilma Rousseff. The charges against him are expected to weaken his hand.

Others caught up in the prosecutors' net include the billionaire head of global construction company Odebrecht and a navy admiral once tasked with overseeing a secret nuclear program.

Even Rousseff's presidential predecessor, Workers' Party hero Luiz Inacio Lula da Silva, is being investigated in an unrelated influence peddling probe.
A former top aide of Lula's was arrested this month on accusations that he was a chief instigator in the Petrobras scheme.

Rousseff herself has not been accused but she chaired the board at Petrobras between 2003-2010, when much of the alleged corruption was flourishing.

The treasurer of the Workers' Party was among those arrested in April.