A Brazilian judge has accepted charges against former President Luiz Inacio Lula da Silva for allegedly obstructing the corruption probe at state-run oil giant Petrobras. The date of the trial has not yet been set.

The decision published on Friday names Silva and five others as co-conspirators in an alleged attempt to buy the silence of a former Petrobras director implicated in the scandal.

The obstruction-of-justice accusation against Silva comes from a plea bargain testimony by Sen. Delcidio do Amaral.

On Thursday, Silva's lawyers filed a petition at the U.N. Human Rights Committee alleging a lack of impartiality and abuse of power by another judge investigating the Petrobras scandal.

Silva leads the polls for the 2018 presidential elections.