( CNN ) -- They have blown out in spectacular style and drawn criticism from one of the world 's top drivers , but Pirelli insists there is nothing wrong with the tires it supplies to Formula One . Pirelli came under intense scrutiny after tire degradation led to four retirements at June 's British Grand Prix , while Ferrari 's two-time world champion Fernando Alonso recently described the tires as `` not good . '' Pirelli 's CEO has defended the rubber provided by the Italian manufacturer , suggesting some drivers are not using the tires correctly . `` I have to say that he was very nervous when he said that , '' Marco Tronchetti Provera told CNN when asked about Alonso 's remarks at October 's Korean Grand Prix , which was won by newly-crowned drivers ' champion Sebastian Vettel . `` It was not because of tires -- he was n't able to win for a number of reasons . If they did n't use the tires properly , it 's not our fault . '' Pirelli is in the third year of its agreement to supply tires to F1 , and Tronchetti Provera does not rule out the possibility of extending the company 's deal beyond 2015 . He warns that , if the working relationship between F1 and Pirelli continues , teams should pay attention to the advised limits of each tire compound . With F1 bosses asking for tires not to last as long , in order to make the racing more exciting , pit-stop strategies have become more important -- and teams have been pushing tires to the limit in their search for an advantage . `` We can do whatever is needed , but with the respect of the rules , '' the 65-year-old said . `` It means tires have to be used within the limits we provide teams . '' While Pirelli 's reputation in the paddock might have taken a knock , Tronchetti Provera insists the brand itself has not adversely affected by its association with F1 -- earning $ 1.5 billion on sales of over $ 8 billion last year . `` We had some damages for a few weeks after Silverstone , '' he admits , `` but I think today people understand it was n't Pirelli 's fault . '' The 2013 F1 season continues with the United States Grand Prix in Austin on November 17 , before coming to a close in Brazil seven days later .
Pirelli CEO defends the tires the manufacturer supplies to Formula One . The company has been under fire for its handling of tire safety issues in recent years and is now facing a class action lawsuit from former drivers who claim they were injured by their tires. Ferrari 's Fernando Alonso described the tires as `` not good '' Pirelli is in the third year of its F1 deal and likely to continue in 2014 season .