Sebastian Vettel has mere days to decide if he wants to join the Racing Point team - set to become Aston Martin - in 2021.

That is the claim of Auto Bild correspondent Bianca Garloff, reiterating that the July 31 deadline ties in with a clause in Sergio Perez's current contract.

On July 31, Friday practice for Silverstone's back-to-back races kicks off.

"According to our information, Vettel only has to agree. Then he has the seat," Garloff claims.

Mercedes boss Toto Wolff, who recently bought into Lawrence Stroll's new Aston Martin project, encourages the quadruple world champion to sign up.

"Sebastian is a four-time world champion with a lot of speed and technical experience," he said. "He would also be an important marketing tool for Aston Martin."

However, former F1 driver Nick Heidfeld thinks his fellow German is facing "a very difficult decision".

"He initially said that he only wanted to continue with a top team, but now he says he just wants a 'good package'," Heidfeld told Sky Deutschland.

"For me, this means he has opened the door to wanting to definitely stay in Formula 1."

Vettel would also get a 'pink Mercedes' to race next year, Heidfeld said, and "If you look at Ferrari's current performance, Aston Martin would be an improvement".

"I think it is a good medium term option for him," said Heidfeld. "The Mercedes engine is a good fit as well, but Sebastian would be a big help to the team.

"With his experience, Sebastian can undoubtedly make the difference for any team with serious ambitions."