LONDON — Lewis Hamilton rejected F1 boss Bernie Ecclestone’s assertion on Thursday that racist abuse directed at the driver probably started as a joke.

F1’s first black champion was the target of racist abuse on a Spanish Web site and endured other insults in the buildup to last Sunday’s Brazilian Grand Prix. Hamilton’s father, Anthony, said he had often considered withdrawing the 23-year-old driver from the sport because of the abuse.

“(It was) probably beginning as a joke rather than anything abusive,” Ecclestone said Thursday in a radio interview, pointing to poor sportsmanship rather than racism by Spanish and Brazilian fans. “I don’t see why people should have been (insulted by it). These things are people expressing themselves.”

Hamilton disagreed and said he “didn’t see it as a joke.”

“It’s something that happened, but it is in the past, you’ve got to look forward,” said the McLaren driver, who clinched the F1 title by a single point over Ferrari’s  Felipe Massa.

In the week leading up to the Brazilian race, Hamilton was the target of racist abuse on a Spanish Web site, was insulted by two Brazilian comedians and was handed a black cat — a symbol of bad luck in Brazil — at a sponsor’s function.

Last February, a group of people at testing near Barcelona wore dark face paint with T-shirts displaying the slogan “Hamilton’s Family.” Hamilton has become a target for many Spaniards who believe the British driver derailed Fernando Alonso’s championship hopes last year.

“I don’t think we should even be talking about racism,” Ecclestone had told The Associated Press at the time. “I really think that they are against Hamilton for his ability, not because he is black. I always thought it was a bit of a prank — they’re probably not racist at all.”

In other news, Hamilton said he plans to spend the rest of his career with the McLaren racing team. Hamilton, who has a $120 million, five-year contract with McLaren, said he couldn’t envision driving for another team.

“It’s easy,” he said. “I’m with the team I’ve always dreamed of being with, and if you have the car of your dreams, then why would you want to leave? The day I get in the car and don’t have the motivation, maybe that’s the time to get out. But I want to see my career out with this team.”

Hamilton’s visit came the same day he received a congratulatory message from Queen Elizabeth II. He returned to Britain after finishing fifth in the Brazilian Grand Prix on Sunday, taking the season title by one point ahead of race winner Felipe Massa of Ferrari.

“We have proved to everyone that we are the best team and we have the best car,” said Hamilton, who is F1’s first black champion. “We have been under so much pressure and we have lost together and won together, and this weekend we have won the world championship.”

Hamilton shook hands and posed for pictures with employees amid a shower of confetti. His father, Anthony, and pop singer girlfriend Nicole Scherzinger also attended the event.

“These trophies are a result of all your hard work and you should pat yourselves on the back,” Hamilton said. “I love this team. I’m not going anywhere.”