Gerhard Berger is not optimistic that Sebastian Vettel will still be in Formula 1 next year.

Already this week, the F1 legend - who was team co-owner when Vettel won his first grand prix in a Toro Rosso - has invited the German to switch to DTM.

"Seriously, why not?" said the German touring car series' boss.

Berger also said he is not surprised that Vettel and Ferrari have decided to split after 2020.

"You could see it coming," the Austrian told Sport Bild.

"But he doesn't have to blame himself. He joins many drivers who failed to get Ferrari back on the winning track. Gerhard Berger was one of them," he smiled.

"But as a four-time world champion Sebastian will easily be able to cope with it. There are very few who have been so successful."

Some think Vettel, 32, is now inching towards retirement, but Berger thinks the German actually wants to keep racing.

"He wants to drive in a top team, but only at Mercedes is it possible. And I'm afraid that the seats are occupied there too," he said.

Finally, Berger says he is happy that his country is the one that will kick off Formula 1's return to action with two 'ghost races' in July.

"Is it thanks to the persistence of Red Bull, Didi Mateschitz and Helmut Marko," he told Austria's Kronen Zeitung newspaper. "On the one hand, they have the potential, but above all the ability to deliver."