Cunha, who was recently stripped of his parliamentary privileges, was accused of receiving kickbacks from Petrobras contracts, including for two drillships built in South Korea for state-run Petrobras.

He is said to have stored the proceeds in secret Swiss bank accounts, the existence of which was denied but subsequently proven.

Cunha has denied the bribery charges and used his formidable knowledge of congressional procedures to hide behind parliamentary privilege as long as possible.

Cunha