The leave, which Machado has called voluntary, will now extend to 20 March 2015, Petrobras said in a statement.

Transpetro executive director Claudio Ribeiro Teixeira Campos will continue to lead the shipowner in Machado’s absence.

The extension of Machado’s unpaid leave was agreed at a board meeting of Transpetro in Rio de Janeiro on Thursday.

Former Petrobras downstream director Paulo Roberto Costa has told government investigators that Machado offered him BRL 500,000 ($191,000) in kickbacks for agreeing to charter Transpetro ships in 2009 or 2010.