Brazil’s governing Workers Party has suspended its former leader in the Senate, Delcidio Amaral, who was arrested last week.
He was accused of obstructing investigations into a major corruption scandal at the state-owned oil company, Petrobras.
Mr Amaral has been suspended for 60 days, but influential party leaders had called for his expulsion.
The Workers Party has distanced itself from the senator since his arrest.
An internal investigation will decide whether Mr Amaral should be expelled.
The senator had been secretly recorded apparently discussing plans to help a detained official flee the country in return for not implicating Mr Amaral in the scandal.
The official, Nestor Cervero, was accused of masterminding the corruption scheme. He signed a plea bargain agreement with prosecutors.