Pat Symonds has revealed it was out of "misguided devotion" to Renault he engaged in one of sport's greatest conspiracies.

Symonds' thoughts behind an incident that has shamed Formula One has come to light via documents and findings released by the FIA following Monday's World Motor Sport Council hearing into the race-fix scandal surrounding last year's Singapore Grand Prix.

After 33 years in motor sport, Symonds has paid dearly for such mis-placed sentiment, initially by losing his job as Renault's executive director of engineering last week.

However, he has also been handed what effectively amounts to a five-year suspension from motor sport as the FIA will not sanction any event should Symonds be involved.

The ban was less stringent as opposed to the unlimited suspension period for Flavio Briatore in recognition of his admittance that a conspiracy with former driver Nelson Piquet Junior to crash his car during the sport's first night race did occur.

The FIA has released a letter written by Symonds, and addressed to the Council, which was read out during the meeting in mitigation.

Symonds wrote: "I was the one who, when the idea was first suggested to me by Nelson Piquet Jr, should have dismissed it immediately.

"It is to my eternal regret and shame that I did not do so.

"I can only say that I did it out of a misguided devotion to my team, and not for any personal gain whatsoever.

"I consider the role I have played in bringing the team to where it is today to be my life's work.

"I started the nucleus of the team 28 years ago with only 19 other people.

"Today it has grown to an organisation that directly employs over 500 people and supports innumerable local and international businesses.

"The last thing I ever wanted to do was to jeopardise that team and the many people to whom I had an overwhelming responsibility.

"In a single action I have destroyed the high reputation I have built up during a 33-year career in motor sport.

"I am a competitive person who worked in a high pressure environment. This can, at times, cloud one's judgement.

"On that night in Singapore last year I made a mistake the consequences of which I could never have imagined at the time.

"For that mistake I can only offer all of you, and all those touched by the action I was involved in, my profound apology."

In his letter Symonds insists the idea to crash was "entirely conceived" by Piquet Jnr.

That is at odds with the Brazilian's version of events as he maintained he was approached by Symonds and Briatore.

As to who was the initial perpetrator of the scheme was not debated by the Council as the conspiracy itself was the over-riding subject matter.

It has emerged Briatore's fate was sealed on the evidence of a secret whistleblower within Renault, codenamed 'Witness X', who came forward during the team's own internal investigation.

Granted the right of anonymity to protect his identity, Witness X's testimony helped the Council dismiss Briatore's suggestion he had no knowledge of the affair.

They also refused to accept his version of events before ruling he was "personally and directly involved in the planning of the conspiracy," resulting in his severe punishment.