MONTREAL, June 5 (Reuters) - Ferrari's world champion Kimi Raikkonen refused to rule out retiring from Formula One at the end of next year on Thursday but said he intended to keep racing for as long as enjoyed it.

"There have been rumours like that for many years," the Finn told a Canadian Grand Prix news conference when asked about the possibility of him retiring when his contract expires at the end of 2009.

"I always say that I still have a contract until the end of next year," he said.

"I haven't made any decision as to whether I will keep going or not," added the 28-year-old. "That's the last contract that I have and we will see during this year and next year what happens."

Raikkonen joined Ferrari at the end of 2006 as a replacement for retired seven times world champion Michael Schumacher and won the 2007 title by a single point from McLaren's Lewis Hamilton and Fernando Alonso.

The Finn has won two races so far this year and is currently second overall, three points behind Hamilton after six races and one ahead of Brazilian team mate Felipe Massa.

"I wouldn't stop if I thought I would miss it," Raikkonen said of the decision facing him. "For sure I would find something else to do, something maybe that you enjoy even more."

"I don't know what is going to happen after next year, I haven't made my mind up. Maybe either we make the decision this year or maybe not."

"I think I am going to race as long as I enjoy it, I think it's the right thing for me, and then when the day comes when it's no longer fun, then for sure I stop," he continued.

"It can be the end of next year, it can be in four years' time. It is too early to say."

ALONSO SPECULATION

Raikkonen's future at the team has been the subject of considerable speculation along with that of Spain's double world champion Alonso.

Ferrari president Luca di Montezemolo has ruled out an Alonso-Raikkonen partnership, saying that would only damage the team, but the Renault driver is likely to be high on their list should the Finn decide to walk away.

Raikkonen, who joined Ferrari from McLaren, said last year that driving was the only thing he loved about Formula One and that he would quit if he had to deal with everything else in the sport.

Ferrari have kept the demands on his time to a minimum however and Raikkonen said when he won the title in Brazil last October that the Italian team felt like a family to him and that he enjoyed every moment with them.

"I like the racing and all the other stuff is not always the best thing," he said on Thursday.

"Everyone in Formula One is here because of their love of racing and driving. When there are too many things that you don't enjoy or you think that the whole thing is not what you want any more, then it's time to go away."

Raikkonen said he was unlikely to move to any other team from Ferrari and was 'kind of' in talks with them for an extended deal.

Asked whether he wanted to win back-to-back championships, he added: "I will try to win them but if I don't win, I have won one and it is not the end of my life."

(Writing by Alan Baldwin in London, editing by Padraic Halpin)