Rosberg says his future remains open

The Williams driver had said earlier this year that the form of his team during 2009 would be crucial in his decision on whether to continue at the British squad or move somewhere else.

Rosberg said in February that he wanted to be in a race-winning car by 2010 "at the latest."

Although Williams has enjoyed a promising start to the season, the German driver has scored just 4.5 points in the first five races.

Rosberg admits he feels at home at Williams, but he insisted he wants to be in car that can win races.

"I'm looking at it now. I'm trying to build an image in my head about what possibilities are for next year," said Rosberg when asked by AUTOSPORT about his future.

"That fact is I feel really good in this team. They support me, and we've grown together, so it's a nice feeling here. So it would be nice if I could stay, to develop the car together that would be great."

He added: "It would be great to have one (race-winning car) now, but in F1 there's only two teams that have race-winning machines if anything.

"So you just need to be patient. If you deserve it sooner or later it will come and next year is going to be an important stop for my career.

"I would like to find something which is a good, long-term solution. It's important to get it right.

The 23-year-old said he had been encouraged by the progress made by Williams this year, and he reckons his speed at the Spanish Grand Prix, the first race in Europe, is a good omen for the rest of the season.

"It's very encouraging that we are in this position at this track, because it means that we can definitely compete in terms of development with the other teams and we have a chance to stay where we are or maybe a little bit better for once. So it's okay," he added.

"It's a good platform. They have done a good job with the development to put us in this position again, so it's okay.

"Over the winter they have shown they can build a good car. They've developed well through the first few races. So we'll see."

AUTOSPORT understands Rosberg has already begun talking to other teams to find out what options there are for next year.