McLaren's new Formula One car should make its testing debut before the end of this month, team partners Mercedes said on Saturday.

"If everything goes according to plan, the new car should be driven for the first time in the 48th week (of the year)," Mercedes chief Juergen Hubbert told guests at a Mercedes party in Stuttgart, the German carmakers' home town.

McLaren hope the MP4-18, which they describe as revolutionary and whose debut has been postponed several times, will help them challenge the supremacy of world champion Michael Schumacher's Ferrari team next season.

McLaren's Kimi Raikkonen narrowly missed out on the title this year, finishing second, two points behind Schumacher. McLaren ended third in the constructors' standings behind Ferrari and second-placed Williams.

"Overall it was a successful year," said Mercedes motorsport boss Norbert Haug. "If we keep improving, we will soon be where we want to be. We are not afraid of anyone, and that goes for Ferrari and Williams."

Raikkonen also looked to 2004, saying: "It was a good season, even if it's obviously better when you're at the very top. I can't promise I will be champion next year but that certainly will be my goal."