Hockenheim boss Georg Seiler has admitted that the future of the German Grand Prix is not secure beyond next year.

Amid the Nurburgring's troubles, the country is not on the calendar this year, but Hockenheim is at least scheduled to host the race in 2018.

However, Seiler told German news agency DPA: "We will not conclude a contract for the future that involves any risks."

He is referring to the fact that the existing contract, an alternating scheme devised by Bernie Ecclestone, has nonetheless put financial strain on Hockenheim.

"From an economic point of view, we had to accept losses through Formula 1, which had a significant impact on our results in recent years," he said.

"We also do not get a single euro of subsidy from the region, country, federation or anyone else, unlike just about every other race track."

When asked if there will be a German Grand Prix in the future, he answered: "For me it's clear. We have a contract for next year, but after that not.

"If we follow the previous rule, 2019 it would be the Nurburgring's turn and us in 2020 again. But only if the contract fits. If the basic conditions do not change, the future of Formula 1 in Germany is certainly at risk.

"If we can at least break even, that would be alright. But if there is no more Formula 1, then so be it. However I hope and firmly believe that the new [F1] owners have an interest in having a German Grand Prix.

"Germany is an important market for Formula 1, no matter what circuit it takes place at."

The German Grand Prix has been a fixture on the Formula 1 calendar since 1951.