Scott Speed appears to be on the verge of quitting Scuderia Toro Rosso - if he hasn't already been given his marching orders - claiming that he can no longer work with team principals Gerhard Berger and Franz Tost.

Speaking to, the American claimed that 'you couldn't pay me enough money to race for those two people again' as simmering tension between STR and both its drivers came to a head at a dramatic European Grand Prix on Sunday.

Speed and team-mate Tonio Liuzzi were both caught out by the sudden change in conditions early in the race, ending their challenge in the barriers at turn one. But, when the American returned to the pits, he was confronted by Tost, with a verbal exchange turning physical.

"Initially I didn't want to come out in the press because, after the race, Franz spent 15 minutes apologising for his behaviour," Speed said, "But, after coming out and denying this stuff, it's just another very dishonest thing that Franz or Gerhard have said in the media to damage me and Tonio. And, at this point, I've had enough. Franz Tost, in particular, is out of control.

"The fact of the matter is, when we left the pit wall, Franz was furious that I'd crashed - regardless of the fact that nearly every single driver behind [Jenson] Button did the exact same thing, including Lewis Hamilton and Nico Rosberg. He was furious that I crashed.... and he didn't want to hear any criticisms about what the team did [at the preceding pit-stop]. After that, I just turned away and walked towards the garage, and I guess he must have caught up behind me. When he reached me, he hit me in the middle of the back with a closed fist. Everyone in the team saw it. As I was leaving the garage, he then followed me behind the partition, where none of the mechanics could see. He grabbed me from the front of my shirt, jerked me around, ripping my firesuit a little bit, and pushed me against the wall. After that, my only response was to back up in the middle of the garage and ask him if he wanted to hit me in front of everyone else."

Despite the attempt at reconciliation, Speed remains convinced that Tost and Berger would be happy to see the back of both him and Liuzzi - and will continue to undermine the drivers' credibility.

"It was very clear that they have a different expectation of what they think is possible to do in the cars, and they are going to continue to point the finger at us drivers until they get the change that they want," he claimed.

While admitting that his future with STR is limited at best - with Sebastien Bourdais being lined up for 2008 and Sebastian Vettel possibly replacing the American from Hungary onwards this year - Speed insists that he is more concerned that his relationship with sponsor Red Bull may have been harmed by the goings-on.

"Franz Tost and Gerhard Berger have been pushing the same dishonesty to the media, and I'm worried that might have ruined my relationship with Red Bull," he confirmed, "Red Bull has been amazing to me, and I think we fit together really good, and it's a shame to let these two people ruin the whole thing.

"As far as my future in F1 is concerned, you couldn't pay me enough money to race for those two people again. If it was with a different team, that would be great, but I would also like to do something else with Red Bull, even if it was outside F1."