Kimi Raikkonen has fewer worries after comeback test at Valencia last month

The 2007 world champion, speaking at the launch of the new Lotus E20 at Jerez, said that while Pirelli's tyres were always going to provide his steepest learning curve, he felt that his run on the demo rubber in a two-year-old Renault had displaced any worries about getting up to speed quickly.

"The tyres are probably the biggest difference since I left, and that's what people were saying," said Raikkonen. "But since the test two weeks ago I have less worries about the whole thing than I had before.

"So we will see where we are when the first race comes.

"For me it was nice to get back in the car again. It is very difficult to say how well we went, but I got back all the feeling about driving the car and got used to working with the team. That was really the main goal, to learn.

"It was interesting to drive and get a little bit back that feeling."

Raikkonen, who shook the Renault-powered E20 down during a team filming day at Jerez on Monday, said that in the short period of time that he had been working with Lotus he had been convinced that all the ingredients were in place for the squad to return to a championship-winning level.

"Nobody knows exactly [how long it will take]," he said. "The team has a lot of hunger to do well and to get back their winning ways but it's not easy. If it was, everybody would do it. But definitely there are people who want to get back there and put in the effort for it.

"They have won it before so they have all the tools to do it. It's just about getting everything right and being up there all the time so hopefully it can happen soon, but everybody seems hungry to do it."

Raikkonen said that he was not expecting many changes on his return and that many of the faces in the paddock were similar to those he had left behind when he walked away from the sport at the end of 2009.

Responding to a question that suggested he was no longer enjoying the sport when he left, Raikkonen replied: "That was only your opinion, I would have left earlier if I wasn't having fun.

"I always said that I loved the racing and I have always been very happy to race. There were a lot of stories from all of your [the press] side about my motivation, but I never had any issues with that. This has come from nothing from my mind.

"I don't think I look at Formula 1 any differently," he said. "It's a new year and there are some different things from in the last few years, but I know the sport, I know how things work here.

"The racing is going to be a little different but all the other things are more or less the same. OK from team-to-team it changes in things outside of the racing but I feel sure it is going to be similar experience."