Nelson Piquet Jr claims his former team Renault had "threatened" to withdraw his contract unless he agreed to purposefully crash during the 2008 Singapore Grand Prix.

In what has become known as 'crashgate', the French manufacturer was last month found guilty of causing an accident to help the chances of their driver Fernando Alonso, who went on to win the race.

The allegations cost former Renault team principal Flavio Briatore and executive director of engineering Pat Symonds their jobs. Renault were also given a disqualification suspended until the end of the 2011 season.

The 24-year-old regrets agreeing to the conspiracy but in an interview with Brazilian television, Piquet Jr said his Renault contract was under threat unless he agreed to the crash.

"Some people have suggested that I was blackmailing Renault to continue my career but the situation was more complicated," he said.

"At each race it was always the same story of threatening to withdraw my contract.I made the allegation so that no other driver would go through what I did."