BMW Sauber's Nick Heidfeld has said that he is 'not concerned' that he has yet to sign a new contract with the team, even though his current two-year deal expires at the end of this season.

Heidfeld is currently enjoying his best season to date in Formula 1 and thus far he has notched up 33 points, thanks to seven points finishes from nine, including a runners-up spot at the Canadian Grand Prix last month and three fourth places.

Despite that though there is still no news on if he will stay with the team in 2008 - and the last that was heard from BMW Sauber team boss, Mario Theissen on the matter, was back in May, when Theissen said that while there was 'no reason for either of party to be looking elsewhere', at the same time there was 'no rush to sort things' out either.

When asked if he was bothered about still not having been given a new deal, Nick replied: "Not especially. I've been through far tougher times. I'm not concerned about the situation."

Pressed on why team-mate, Robert Kubica always gets much of the praise and attention, Heidfeld added that is just normal: "Last year, it was just a typical Formula One situation. New drivers are always hyped up at first, but that settles down after a while. I believe I am well thought of in Formula One," he added.

As for the current form of the team, Nick noted that in some ways he has been shocked by the way they have made so much progress.

"We have exceeded expectations," he explained. "I was sure that we would step up a level in our second season on the grid - but having said that, we finished fifth in the constructors' standings last year - 50 points off fourth place - and there was no way I could have expected us to be the third-best team already."

So why have they managed to go forward so quickly?

"We already had a good group of people on board, but now we also have the resources of a leading team," he continued. "We've brought in 150 new people at our Hinwil base, the wind tunnel is in use around the clock, we are better equipped at the race track, and a programme of expansion is under way at the factory in Hinwil. It's something of a building site at the moment, but the work will be completed by the end of the year."

The big question though is when will BMW Sauber be able to challenge Ferrari and McLaren-Mercedes for victories? Nick believes it is 'just a matter of time': "The F1.07 is, in effect, the first genuine BMW Sauber. Even more experience and resources will go into next year's car. We are heading in a positive direction," he summed-up.