Flavio Briatore (File)

Paris - Team chief Flavio Briatore on Wednesday sensationally quit the Renault Formula One team, which has been hit by serious allegations of cheating at last year's Grand Prix in Singapore, the team announced in a statement.

Renault said in a short statement that Briatore and Pat Symonds, the director of engineering, had both left the team ahead of a meeting Monday with the sport's world ruling body the FIA to explain recent allegations of race-fixing.

The statement said: "The team announces that its team chief, Flavio Briatore, and its director of engineering Pat Symonds have quit the team."

Renault have been summoned to appear before the FIA's International Motor Sport Council in Paris on September 21 to answer claims by Nelson Piquet junior that he was asked by Renault to crash deliberately during the 2008 Singapore Grand Prix, so giving a race-winning advantage to his team-mate Spaniard Fernando Alonso.

If Renault are found guilty of race-fixing, they could be expelled from the sport for the role they played in an affair which has been dubbed 'Crash-gate'.

The team had denied all of the claims made against them by Piquet junior, who was dismissed by the team in July after being told he had failed to perform to expectations.

But on Wednesday Renault appeared to partly admit some role in the controversy by adding in the statement they "would not contest the FIA's recent allegations concerning the Singapore Grand Prix".

The statement added: "Before participating at the FIA's International Motor Sport Council hearing in Paris on September 21, the team will make no further comment."

A report by The Times on Tuesday, citing unnamed sources, claimed the FIA had offered Renault second-in-command immunity from punishment in exchange for full disclosure about 'Crash-gate'.

The report said that Symonds was told that if he came clean over how and why Nelson Piquet junior drove his car into the barriers in Singapore in 2008, he would escape sanctions.

Former driver Piquet and his father, three-time world champion Nelson Piquet senior, claimed that Renault conspired to fix the outcome of last year's race.

At the Grand Prix on September 28, 2008 Alonso began the race in 15th position. But after making a very early pit stop to refuel, Nelsinho Piquet junior crashed into a wall, prompting the safety car out.

As Alonso's rivals then gradually disappeared into the pits to refuel, the Spaniard catapulted himself up into the virtual lead to go on and win his first race in a year.

In response to the allegations Renault accused Piquet of blackmail and announced they were launching criminal proceedings against him and his father.

Briatore denied all the accusations against him -- notably conspiring with team management and Piquet to cause a deliberate accident -- saying they were "outrageous lies".

Stewards investigating the claims interviewed Symonds at the Belgian Grand Prix late last month.