Ferrari's Fernando Alonso has heavily criticised the tyres used in Formula 1, saying they are "not good" and so fragile drivers cannot push hard.
He said the Pirelli tyres "will not do 5km" - about the length of an average lap in F1 - and were "not normal".
"We have to be honest; the quality of the tyres is very on the limit."
"If all the cars push 100% from the start of the lap, the tyres will not do 5km. It is not very helpful and not very nice to drive at 95% all the lap."
But Alonso made it clear he was not saying the Pirelli tyres were the cause of Ferrari's lack of performance, adding: "If we put a tyre that can do more than 5km, they will be even faster as well."
He said he merely wished the sport had tyres that allowed drivers to push to the limit.
"It is not normal," he said. "If you push, you finish the tyres.
"We are getting used to these tyres that cannot last one lap. We are getting used to marbles [bits of discarded rubber] that [mean] we have two metres [width of] racing line.
"I'm sure with a better tyre the others can push more as well. The deficit we have is the same with any tyre, but at least you could drive."
Pirelli has been asked by F1 boss Bernie Ecclestone to produce tyres that create multiple pit stops in a race and the possibility of different strategies to create more entertaining racing.
Pirelli motorsport director Paul Hembery said: "Of course Alonso is one of the great F1 drivers, so to hear such comments is disappointing and below the standards you would expect from such a champion.
"I can only suggest he goes to ask the soon-to-be four-times champion how to get the best from the same tyres."
For Korea, Pirelli has supplied the softest and least durable of its tyres - the 'super-soft' - and the more durable 'medium'. The drivers all set their fastest qualifying time on the 'super-soft'.
But Alonso is the latest in a string of top drivers to criticise the tyres for being too fragile and not allowing drivers to push to the limit.
Alonso said he was less confident than normal that he could make up ground from his grid position, as he usually does.
"This weekend we are not particularly strong," he said. "[Not only in qualifying, but] also in the race pace we saw some problems.
"So I'm a little bit less optimistic in terms of winning the race or podium finish.
"[It is] nothing really new. We have been four years in this situation - we are lacking between half a second and one second [in] pace and we have been still fighting for the championship to the last race in two of the last three seasons.
"We have some weak points and strong points. One of the strong points is scoring maximum points in the race. We cannot forget that and try to do so on Sunday."