Ferrari's Vasseur says he talks to Hamilton at every race

Ferrari team boss Fred Vasseur has spoken about his friendship with Lewis Hamilton as Formula One waits for the seven-times world champion to sign a new contract with Mercedes.

Hamilton won Formula Three and GP2 (now Formula Two) championships with Vasseur's ART team in 2005 and 2006 before making a spectacular Formula One debut with McLaren in 2007.

"I talk to him at every GP, he raced for me 20 years ago and we are still close," Vasseur, who joined Ferrari in January, told Italy's Gazzetta dello Sport newspaper.

"Clearly, if they (the media) see us together in the paddock, there's a lot of fuss, but the relationship has remained.

"I don't want to compare him to our drivers, it wouldn't make sense."

Hamilton, 38, was linked to Ferrari in paddock speculation earlier this year but the Briton has been clear he wants to stay at Mercedes.

Vasseur said Ferrari's Charles Leclerc and Carlos Sainz could do better, as could the team as a whole in a so-far underwhelming season.

Red Bull have won every race and Ferrari are fourth overall, with just three podium finishes by Leclerc to show for their efforts.

"Charles didn't expect a season like this and at the beginning he pushed more than he should, now he seems to have digested the situation better," said Vasseur, who described the Monegasque as 'impulsive'.

"If something does not go well he does not hold back. However, for his and the team's sake, sometimes it's best to calm down before speaking," he added.

"Carlos is very consistent and for this he is a good reference for us."

Vasseur said Ferrari halted wind tunnel work on this year's car at the end of July but would be adding upgrades until Qatar or Austin in October.

He said some 25 new staff had been hired so far, one known to be