Michael Schumacher has insisted he is "99.9%" certain to end his career with Ferrari.
The seven-time world champion, whose Ferrari contract runs out at the end of this year, has been linked with big-money moves to Red Bull and Toyota for 2007.
Schumacher must decide whether he wants to hang up his helmet following the most successful career Formula One has ever known, with an announcement expected in the summer.
He has frequently stated his desire to end his career at Ferrari and on Thursday confirmed that plan, while not entirely ruling out a swansong with a rival team.
"I said that at mid-season I will decide if I want to go on or not go on, and 99% I do this with Ferrari if I go on," he said. "I should say 99.9%.
"When I said this sentence I made the comment that unfortunately I would rather say this because I don't want to lie and in life it is simply impossible to be 100% certain of what is going to happen. Therefore I see my future with Ferrari.
"Anyway, who can look so far in advance? And who can tell what is going to happen, particularly in our sport where things sometimes move rather quickly.
"As I said, I don't want to lie and therefore I am saying the truth and 99% that is what it is and then we will see."
If 2006 proves to be Schumacher last year in Formula One, the German wants to go out with a title win.
He has broken with tradition to take an active part in winter testing after a disastrous 2005 and he is encouraged by Ferrari's progress.
Schumacher said: "We seem to be on the right pace at the moment. In a way, we are surprisingly quick compared to the others, due to the good work that we have been doing for a long time.
"I think we can only have one target and that is to win the Championship, in particular after a year like last year where success was so poor to our standards.
"We would really like to come back to where we have been before, to fight for the Championship and maybe finally win it."