After a gap year, the German Grand Prix might be back this weekend but the future of the country's place on the calendar remains in doubt.

It was the Nurburgring that caused Germany's 2015 absence and it seems that the circuit remains unable to continue its alternating scheme with Hockenheim.

"We have a contract for 2016 and 2018 and other than that it is not our turn," Hockenheim chief Georg Seiler told the German news agency SID.

Beyond 2018 is also in doubt, he added.

"Of course we want to keep Formula 1," said Seiler, "for the image of the circuit as well. But it must be at a level that works economically."

New Nurburgring chief Mirco Markfort also expressed interest in Germany's F1 future but said that the problem is money.

"We would love to host the German Grand Prix," he said, "but for this the right economic conditions must be present. We cannot afford Formula 1 at any cost."

Hockenheim's Seiler said the problem is that new hosts like Azerbaijan and others are driving up the average annual race fees.

"If there were 20 countries that would pay EUR 50 million for a race, then the season would probably only take place in those countries," he said.

"But for us there is no such public pot. We need to rely on the fans."

The halcyon Michael Schumacher days, however, are over, and Seiler said Hockenheim's audience is now "older" than before.

RTL, the German broadcaster, said Hockenheim has so far sold 52,000 tickets for Sunday's race, down on its target of 60,000.