Pirelli frustrated its McLaren Austin tyre test plan was refused

Formula 1's tyre supplier is eager to finalise its 2014 products, but has been forced to find an alternative venue amid concerns that McLaren's running ahead of the United States Grand Prix could give it an unfair advantage.

Pirelli motorsport director Paul Hembery said efforts were now focused on seeking out an alternative venue, but is unhappy that a bid to get fully prepared for next year has been thwarted.

"It is not ideal obviously - that is a bit of an understatement," he said. "We understand that there were some objections from a couple of teams, and that is part of the process to make sure that you don't cross over any boundaries after the Mercedes test.

"That is why you have the process of approval and the reasons given. So we have to accept them and find another solution."

Hembery says that the dramatic torque increase expected from the 2014 engines will be a challenge for rear tyres next year, which is why he is frustrated that his company is not being given all the help it can get.

"The brief is obviously quite difficult because the real impact for us will be in terms of torque, wheelspin, and a lack of downforce.

"I don't think anybody really knows what it will be like. If we look at the data from the teams, there is a huge disparity, so we need to maybe do another survey in a month's time to see if there have been any updates to that.

"But you can imagine we are not really going to get all the correct data because there is paranoia in F1. All suggestions are that it is going to be a strange start up and a big difference for everybody - drivers, teams and ourselves."