Motivation, not money, was the main reason Lewis Hamilton on Friday confirmed he was to leave McLaren for Mercedes next year.

That became clear in the aftermath of the news that he has signed for fellow-Briton Ross Brawn's Brackley-based team and was turning his back on the outfit that had nurtured his career since he was 13 years old.

Mercedes team chief Brawn said the 'silver arrows' did not break the bank to secure Hamilton's switch from McLaren, a move that has re-booted the Formula One landscape for next season and re-ignited the ambitions of the 2008 champion.

Amid claims that the 27-year-old Briton chose to switch to the German-owned outfit because they were offering far more money than McLaren, Brawn instead claimed that Hamilton took the initiative and made the decision because he wanted a new challenge in his career.

In the wake of the news that confirmed one of the sport's worst-kept secrets, Brawn stressed that Hamilton had shown he was keen to 'do a Schumacher' and join a team that could be moulded around him for the future.

German Michael Schumacher, the legendary seven-time champion who Hamilton is replacing at Mercedes, did exactly that when he joined Ferrari in 1996 and transformed the Italians from also-rans into the greatest force in the pit lane.

Brawn said: "I think for Lewis, the attraction was being part of that building structure - the creation of the team. Not walking into a ready formed, successful package.

"It was being part of the process of building that package. I think he felt that that was the next stage of his career.

"There is a competitive market for drivers and Lewis is as competitive as anyone else in that respect, but he didn't come here because we offered more money - because we didn't."

For Hamilton, the key to the move is that he can escape, at last, from the sometimes claustrophobic atmosphere that has increasingly enveloped him at McLaren where he has been part of the organisation since he was 13.

In the past, he has complained at having felt trapped between the influence of two often overbearing father figures in his life - his own father Anthony, who managed his career for many years - and McLaren's former team chief and now company chairman Ron Dennis.

The arrival of fellow-Briton Jenson Button changed the mood temporarily, but having studied the way in which Button, 32, has quietly remoulded McLaren around his own particular needs, Hamilton has decided to leave rather than fight on.

And, at Mercedes, he will line up alongside a rival and team-mate he knows well in German-born Nico Rosberg, son of the original 'flying Finn' Keke Rosberg.

They were elite karting team-mates in a Mercedes-backed team in the European 'A' series in 2000, a year in which they became close friends and great rivals.

McLaren team boss Martin Whitmarsh believes Hamilton is making a mistake to join the factory team that supplies McLaren with engines.

"Mercedes is a great partner of ours and they are a great team," Whitmarsh said.

"But for anyone leaving McLaren, and he wants to win, I think that's a mistake because I have faith and belief in this team.

"Whether you measure it over the last four races, four years or 40 years, we're a fantastic team.".