Writing on his own website, Michael Schumacher has revealed why he is returning to racing at the age of 40, while warning his rivals that he's "all fired up"

"I have decided to return to Formula One. Mercedes GP and I agreed on teaming up for the coming 3 seasons. And to be honest, I'm already super excited by the prospect to be back in a F1 cockpit.

"I don't want to deny at all that the idea of a German F1 team extremely tempts me," he continues. "I guess every German driver would feel this way. And of course it plays a major role that I again can work together with Ross at Mercedes GP. Above all, however, my old hunger for racing is back. In Abu Dhabi, when Ross asked me if I could imagine returning to F1, I felt that I wasn't ready for it. But only two weeks later, when he called me once again, I realized that my old passion was returning. Suddenly I was on fire again. For me, the imagination to be back in a F1 car and to compete for the world championships is exciting and extremely inspiring.

"That is why my thoughts initially go to Ferrari. I'm very pleased that the split-up goes off that harmoniously and that we are still on friendly terms with each other. I would really like to thank Luca di Montezemolo and the whole Ferrari team big time for the time we spent together and for giving me the opportunity to leave Ferrari in friendship. It's such deeds that make up a true friendship, as even though the contract has not yet been signed, we had promised each other to further cooperate by shaking hands. I will always carry a big part of Ferrari in my heart and I will never forget the sympathy and passion of the 'tifosi'. They supported my all over the world with their devotion - thank you very much for that!

"I didn't take this decision lightly at all, especially because of that," he admits. "Ferrari and I have been working together for 14 years and I've experienced a lot of great moments with the team during this time. Most of my life as a Formula 1 driver is 'red' and so there is strong solidarity and loyalty to these guys who have accompanied me and have always built great cars for me. This solidarity will remain, even though our teams will be competitors on the race track - because I'm certain that Ferrari will regain its former strength since the crew is really strong and committed.

"Mercedes GP will be a new challenge for me which is extremely attractive. I have no doubt at all that the team will be really strong. They showed by winning the two world championships that there is meshing a fascinating mixture of high professionalism and deepest passion. The relation between the competence of Mercedes and the current world champion team is extremely attractive and promises a good performance. I think the duels on the race track will be electrifying. Especially since I've got the feeling as if, for me personally, the circle closes after all the years I spent in Formula One. I concluded my first ever driver's contract with Mercedes - back then in Group C and Le Mans - and Mercedes also supported me when entering the F1.

"Until recently, I was absolutely sure that I had ended my career as a race driver at Ferrari. But sometimes things change suddenly and unexpectedly. All of a sudden, the framework conditions aren't the same anymore. At that point, you have to reconsider the decisions you've made. And, to tell the truth, the failed comeback attempt last summer gave me reason to reconsider my situation. I was surprised myself how fast and how strong I committed myself to this topic again. Apparently, my batteries recharged completely during the last three years. And when - thanks to Ross - the opportunity arose to drive for Mercedes GP, I realized that my old motivation was back, full of fresh energy and great force.

"Physically, I feel absolutely fit. I already realized in summer how fast I achieved my former performance values by exercising specifically. And ever since, I kept on exercising. My neck is absolutely free of complaints. I can now do the same neck work-out as I did when I was still racing. This wasn't possible in summer because back then only five months had passed since my accident and so my neck wasn't cured completely. In the meantime this isn't a problem any more.

"I absolutely enjoyed my current life in those three years, doing a lot of things. There were no bored feelings or something like this, I was doing Karting and Biking without big hassle. Now I am geared up to compete on a serious level again. I know that my change of mind happened rather suddenly and I think it's great that Corinna appreciates my passion and that she absolutely backs me and my decision. When I told her about my plans, she immediately felt that I am serious about it and she instantly gave her approval.

"To put it simply: I'm totally fired up for next year!"