Renault say they are launching legal action against Nelson Piquet Jr and his father Nelson Piquet over race-fixing allegations made against the team.
Piquet Jr has given evidence to the sport's governing body that has led to an investigation into Fernando Alonso's win at the 2008 Singapore Grand Prix.
Renault deny claims they asked Piquet to crash to facilitate Alonso's win and have referred to a "blackmail attempt".
Piquet Jr said: "Because I am telling the truth I have nothing to fear."
In a statement released on Friday, Renault said the claimed blackmail attempt was in relation to "allowing Mr Piquet Jr to drive for the remainder of the 2009 season".
