Brazil’s chief prosecutor Rodrigo Janot is seeking permission to have top politicians from the governing PMDB party arrested, Brazilian media say.
The politicians he wants held are Brazil’s ex-President Jose Sarney, Senate Speaker Renan Calheiros, ex-lower house Speaker Eduardo Cunha and PMDB leader Romero Juca.
The four are suspected of obstructing a massive corruption investigation.
A Supreme Court judge will now have to decide whether to act on the request.
All except Jose Sarney are currently members of Congress, and as such any judicial action against them has to first be approved by the Supreme Court.
The four deny wrongdoing.
They are alleged to have obstructed Operation Car Wash, the investigation into a massive corruption scandal at state-owned oil company Petrobras.
Jose Sarney: Former Brazilian President (1985-1990), preceded Renan Calheiros as Senate Speaker, PMDB
Renan Calheiros: Senate Speaker, PMDB
Eduardo Cunha: Former lower house speaker, forced out over allegations of obstruction of justice, PMDB, driving force behind Dilma Rousseff’s impeachment, was suspended from the post of House Speaker in May over allegations of obstructing justice
Romero Juca: PMDB President, resigned as planning minister two weeks ago over allegations of obstructing Operation Car Wash
The request to have them arrested comes after telephone conversations taped by former Senator Sergio Machado were leaked to the press.
Mr Machado, who used to run a Petrobras-owned logistics company, made the recordings as part of a plea deal with prosecutors.
The investigation has led to dozens of politicians and business executives being accused of paying or receiving kickbacks.
In the recordings, Mr Calheiros, Mr Sarney and Mr Juca can be heard allegedly discussing ways to derail Operation Car Wash.
They have said that their remarks were taken out of context and deny obstructing the investigation.
The leaked recordings cost Mr Juca his post as planning minister.
Earlier, Mr Cunha was removed by the Supreme Court from his post as lower house speaker for allegedly obstructing justice.
Prosecutors now want him arrested because they allege that he continued to try to hinder investigations even after his removal from office.
According to Brazilian media, Mr Janot also requested that Mr Calheiros be suspended as Senate Speaker.
The post is a key one as the Senate prepares to conduct an impeachment trial against Dilma Rousseff, who was suspended from the presidency last month over allegations of manipulating government accounts.
If Mr Calheiros were to be suspended, Senator Jorge Viana would take over as Senate Speaker. Mr Viana is a member of the Workers’ Party and an ally of Ms Rousseff.
Ms Rousseff argues that the impeachment proceedings are an attempt by top members of the PMDB party to oust her from office.
According to Ms Rousseff, PMDB politicians wanted her gone so they could take over power and stop Operation Car Wash.
After her suspension on 12 May, Vice-President Michel Temer of the PMDB became acting president and appointed a new cabinet.
Within weeks of him assuming office, he had lost two of his cabinet members – anti-corruption minister Fabiano Silveira and Mr Juca – to allegations of obstructing Operation Car Wash.
If Mr Janot’s request is granted it would be a heavy blow to interim President Michel Temer.