Finnish Formula One world champion Kimi Raikkonen of Ferrari attends a a news conference at Catalunya's racetrack in Montmelo, near Barcelona in this April 24, 2008 file photo. Raikkonen will return to Formula One in 2012 after signing a two-year contract with Lotus Renault, the team said on November 29, 2011.  [Photo/Agencies]

LONDON - Kimi Raikkonen has said he will return to Formula One next season fully motivated and with his passion for the sport undimmed after two years away.

In a Q+A provided after the announcement of his comeback on Tuesday by the Renault team, who will become Lotus next year, the 2007 champion also saw few problems in re-adjusting.

"I would not have come back if I wasn't motivated," declared the 32-year-old Finn, whose motivation was increasingly questioned during his time at Ferrari after he had won the championship.

"There is always a lot of talk about motivation but nobody really knows what I do or what I think apart from myself so I don't really care about what people say. But I'm happy to be coming back.

"I wouldn't put my name onto a contract if I didn't think I'd really enjoy it -- so it will be interesting and exciting to get back."

Raikkonen has spent the past two years competing in the world rally championship with Citroen and also trying his hand at NASCAR in the United States.

The former Sauber, McLaren and Ferrari driver said he had "never really lost the passion for racing in Formula One, just maybe for all the other things around it".

"When I did some NASCAR races this year I noticed that I was increasingly missing the racing side, to race against each other, because in rallying you really race against the clock," he added.

"And then I got the call from certain people in Formula One. All sorts of things happened and we managed to have a nice conversation with Lotus Renault GP and make a deal -- I'm really very happy with that."

Raikkonen said he had two options, Lotus or Williams, and had started training a month ago to raise his fitness for Formula One and increase his neck muscle strength.

The sport has changed since the 'Iceman' was last racing in grands prix, with Pirelli replacing Bridgestone as tyre supplier and the introduction of the moveable rear wing (DRS).

"I haven't driven and I haven't even sat in a Formula One car since the last race in 2009," said the winner of 18 grands prix. "I'm interested to get back into the car, I'm two years older now and I don't think anything else has really changed.

"At least Formula One is something where I know how everything works as I've been there for many years - compared to rallying when I didn't know what would really happen. Then I went to NASCAR and I had no clue how it would be.

"So in that way it should be much, much easier to come back and it should be pretty normal," he said.