Ron Dennis has ended his 43-year career in Formula One but insisted he was not pushed into quitting in order to save Lewis Hamilton from a Grand Prix ban.

The man who built McLaren into one of British sport's most successful teams has stepped down as chief executive of McLaren Racing, passing that title to long-time lieutenant Martin Whitmarsh, who had already been promoted to team principal in January.

The 61-year-old will now focus on running a new independent company, McLaren Automotive, which plans to launch a new range of road-going sports cars in 2011.

Dennis, speaking at McLaren's Technology Centre in Woking, Surrey, claimed the decision was his alone. “No one asked me to do it,” he said.

He did admit, however, that he doubted that neither FIA president Max Mosley nor Formula One chief Bernie Ecclestone, with whom he has often endured frosty relationships, “will be displeased by my decision.”

The timing of today's announcement has led many pit lane observers to conclude that Dennis is hoping the cutting of all ties with McLaren's racing interests might sway the FIA World Council into going easier on Hamilton and his team when they are asked to explain the Australian Grand Prix Liargate' scandal at a hearing in Paris on 29 April.

Hamilton and sporting director Dave Ryan, who was subsequently sacked after 34 years with the team, were found to have misled officials investigating the manner in which Toyota's Jarno Trulli overtook his British rival for third place in Melbourne while the race there was being run under safety car rules.

Hamilton, who later admitted to lying, was disqualified from the Grand Prix and both he and McLaren could now be banned by the World Council from a number of races or even from the entire world championship.

That would have been the ultimate indignity for Dennis, the former mechanic to Sir Jack Brabham who rose through the ranks to become one of the most successful team owners in the history of Grand Prix racing.

After taking control of McLaren 28 years ago, Dennis steered Niki Lauda, Alain Prost, the late Ayrton Senna and Mika Hakkinen to world titles. But his crowning achievement was the mentoring of Hamilton from kid kart racer to last year's world championship title.

The bond between the fiercely competitive Dennis and the equally driven Hamilton, the first black driver in F1, appeared unbreakable. When Hamilton signed a new five-year contract in January last year, he pledged life-long allegiance to Dennis's team.

That was despite the Spygate' scandal of 2007, Hamilton's first season as a member of the motor racing elite, when McLaren were fined £50million and thrown out of the constructors' championship for possessing technical secrets belonging to rivals Ferrari.

Hamilton and Dennis stood poised to become one of the great sporting partnerships. But while Dennis claimed he took a back seat to the McLaren operation in Australia, it is understood he may have played a significant part in the efforts to get Hamilton promoted to third at the expense of Trulli.

That is said to have caused irreparable damage to Dennis's relationship with Anthony Hamilton, Lewis's father and manager. Both the Hamiltons remain distraught that the driver's carefully nurtured good guy' image has been permanently stained by the lying controversy.

Dennis today insisted his self-enforced absence from the pit lane will be easy to take. He said: “I passed the role of team principal to Martin on January 16th, the day of the launch of our new Formula One car.

“That day I was asked many times whether I would attend the 2009 Australian Grand Prix. My answer was yes'. I duly attended it, albeit not as the person in charge of McLaren-Mercedes. It was, I admit, a strange feeling.

“The next race, the Malaysian Grand Prix, I watched on TV in the UK, an activity I found surprisingly easy. I'd expected to be more emotional about it, after an unbroken run of attending so many Grands Prix for so many years.”

He went on: “I feel enormously enthused about the prospects for the McLaren Group and for McLaren Automotive, and have no qualms about leaving Martin to report to the board regarding matters connected with Formula One.

“With planned additional investment in the company of £250 million, McLaren Automotive's expansion will represent a significant investment in the UK automotive industry.”

Today's announcement does nothing to ease Hamilton's immediate problems of attempting to defend his title with an uncompetitive car.

Whitmarsh has conceded that the decision to concentrate on last year's title battle, in which Hamilton beat Ferrari's Felipe Massa to the championship on the last corner of the last lap of the last Grand Prix in Brazil, meant that development of their 2009 car was delayed.

McLaren and Hamilton are now paying the price on the track. What price they have to pay for cheating in Australia remains to be seen.