Pirelli motor sport boss Paul Hembery has made clear his company’s frustration at the lack of an agreement to continue as F1’s sole tyre supplier in 2014 after its initial three-year deal runs out at the end of this season.

Pirelli has been under pressure from all sides regarding its role in how races unfold in 2013, and the uncertainty over the future has created extra pressure.

The added complication for Pirelli is that the turbo cars will have very different requirements, and until a deal is agreed the company is not in a position to push ahead with R&D.

“Apparently on the first of September we’re supposed to tell them everything that they need to know for the tyres for next season,” said Hembery today.

“We’re now mid-May, so you can imagine how ludicrous that is when we haven’t even got contracts in place. Maybe we won’t be here, anyway.”

Asked whether the chance of the ‘maybe’ had grown since the last race in Spain he said: “Well two weeks have passed, so it’s grown. At a certain point somebody’s got to make a decision.”

Hembery made it clear that without any testing with the new turbo cars it won’t be easy to get the 2014 tyres right.

“I won’t say it will be guesswork. You can get some indications that the power delivery will be very different, the top speed will be different, the aero loads will be dramatically different. There’s a big question on the correct tyre sizes for next year, you’ll have less aero downforce, so maybe you need wider tyres to create grip. There’s a risk of having excessive wheelspin.

“So there’s a lot of parameters there that would create quite a lot of concern, so you’d have to take from my point of a view a very conservative approach, so we’ll be back to no pit stops or one if you need to, and talk about other things.

“The changes are so dramatic, if you go round the teams and ask the teams how they perceive the cars next year you’ll have 11 different answers.”