Pirelli has revealed that F1's tyre tender process for 2025 is "a lot more complicated" than in the past amid an anticipated competition that is likely to include Bridgestone.
A report earlier this month from BBC Sport claimed that Bridgestone had thrown its hat in the ring and entered a bid to become Grand Prix racing's exclusive tyre supplier from 2025 to 2027, with an option for an additional year.
Neither the FIA, which is handling it adjudication process, nor Formula 1 have confirmed Bridgestone's bid, while Pirelli was also formally uninformed of who its competitor would be.
"We don't know who is the competitor," commented Pirelli F1 boss Mario Isola. "Rumours are rumours and I know that formally we don't know."
However, regardless of whether Bridgestone takes part in the tender off or not, the administrative process itself has been difficult and time-consuming task for Pirelli as Isola explained.
"What I can tell you is that the tender document was a lot more complicated than in the past," said the Italian.
"There are many sections and many elements added compared to the last one we applied for.
"There is a big part linked to sustainability, a big part linked to our ability to supply a product with certain characteristics, and a service with certain characteristics, a number of engineers.
'We had to work quite a lot to get all the papers needed for that.'
The FIA is currently reviewing the technical and sporting position it has received from Pirelli and - most likely - Bridgestone, and once completed commercial discussions with the companies will begin, starting a process that could last several months.
Pirelli has been the sport's single supplier of choice since 2011. But teams and drivers alike have often been frustrated with the Italian company's products, pointing to its low resistance to degradation and to overheating concerns.
However, Isola is confident that Pirelli will remain F1's preferred partner, arguing that the company has always responded proactively to the various mandates imposed by F1 and the FIA, while it has also played a significant part in Formula 1's promotion and marketing.
"In these 13 years, we always try to do our best to fulfil the requests we had in different years," Iola explained.
"From 2011 there were high degradation tyres, then we had different power units, and the wider tyre, to the 18-inches. Then more degradation, and then less degradation. We always adapted our product to the different requests.
"On top of that, we have been very active on the promotion side and marketing side, supporting all the requests from the promoter and from the FIA.
"I believe that our role is the role of a partner more than a sponsor. And we would like to be like this.
"We want to be part of the sport not because we want to dictate anything, but because it means that we cooperate in a good way with our stakeholders, plus talking to the drivers and talking to the teams.
"We have built a system that is super-efficient, to supply data to them. I was comparing a report that we did in 2011 with a report we do now and it's incredible [the difference]. You will laugh at the one page we provided in 2011 compared to the book that we provide now.
"All of this is sometimes taken for granted, because when you do that step-by-step, you don't realize how much you have done in this long period."
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