Just days after Kimi Raikkonen admitted that he now sees his F1 career as a hobby, and when it is time to find a new one he will move, former F1 boss, Bernie Ecclestone has said similar of five-time world champion Lewis Hamilton.

Though he rarely gives less than 100% to his racing - hence the titles - Hamilton has his fingers in numerous other pies including fashion, music and movies.

Then there is his coterie of superstar friends from those industries, friends he likes to bring to races, and whose presence is greatly appreciated by the sport's owners who are increasingly looking to move F1 away from sport and into the entertainment and showbiz market.

The sport's former boss however, is unsure of Hamilton, though he recognises his talent and what he brings to the sport, Ecclestone is unsure of his motives.

"Lewis is super and there is no doubt about that," he tells the Daily Telegraph. "Alongside his fashion business, it is almost as if he now treats Formula One as a hobby.

"He is the only real character we have got in the sport," he admits, "it is a pity there are not two or three drivers like him.

"Lewis is the best and worst thing to happen to Formula One," says the Briton. "The best, because he is Formula One. The worst, because he takes so much of the attention for himself and that is not his fault.

"I wouldn't like to think anyone is bigger than Formula One but he is certainly bigger than anyone else, even any of the teams.

"We have a Formula One superstar in England, but do we appreciate him? Probably not," he admits.

Ecclestone also has his doubts concerning Hamilton's main rival, Sebastian Vettel, a close friend of the former F1 boss.

Under pressure from a highly talented teammate who has already won over the media, Ecclestone believes that Vettel could walk away from the sport.

"Sebastian expected to be the number one, and get that support from Ferrari," he says. "But maybe he is now thinking that Charles is going to be the top driver, and that he will have to support him. He won't move over. He won't let that happen."

Asked how the German would react if Ferrari does focus on his teammate, Ecclestone is in no doubt.

"Sebastian would stop," he replies, "and I don't think it would take an awful lot for that to happen. If something upset him enough he would leave. He is happy with his family, close with his two girls, and his wife, so the last thing he would want to do is upset them for Formula One."

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