Pirelli says it does not understand complaints from some Formula 1 teams and drivers that its tyres are more difficult to work with this year.
Haas has struggled to get its tyres into the operating window in races, and team boss Gunther Steiner believes the influence of the tyres is too much, suggesting the thinner-gauge tread introduced this year made it more difficult for drivers to retain heat.
"We spend millions and millions to develop these cars and then they are out of the [tyre] window and really cannot get going," he said.
"I'm not blaming it purely on Pirelli. I'm blaming it on us as well because some [teams] get [the tyres] to work.
"But in general, this is not the right thing. We shouldn't be talking after the race saying, 'Did your tyre work or not?'"
Five-time world champion Lewis Hamilton said before the start of the season he did not think any team was completely on top of how to get the most out of this year's tyres.
But Pirelli racing manager Mario Isola is baffled about why teams think this year's compounds are harder to work with, dismissing suggestions the operating window was narrower than last year.
"If we talk about the width of the working window, and I heard some comments that this year it is narrower, it is difficult to confirm that," explained Isola.
"What we call the C3 and C4 are two compounds that are the same soft and ultra soft that we had last year.
"Obviously the working range is a function of the compound, so with the same compound we have the same working range.
"I don't want to say it is wider, but what I will say is that they can use it at a higher temperature because of a reduction of thickness [of the tread], but we cannot say that it is narrower.
"The C1 and C2 are two compounds that are softer than last year so are more suitable, and the C5 in terms of hardness is the same as a hyper soft, so in terms of mechanical resistance it is better.
"We had a back-to-back comparison in Baku with some teams using the hyper versus the C5, and it is clear that the hyper had graining and the C5 had much reduced graining, so I don't understand where we can say that it is a narrower window."
Isola said he would always listen to the views of teams if they felt improvements could be made, and suggested Pirelli could create a wider window in the future.
"I take any comments coming from the teams on board because narrower or not they are asking for a wider working range," he said. "The result is that they say it is narrow.
"What is clear is that we have to work in the future to have a wider working range.
"We are designing new tyres for 2020 and also for '21 considering the plan to remove blankets [tyre warmers], so we are changing the approach in how we design the compounds.
"We are testing new ingredients and new materials to try to achieve this target, and we will evaluate if we want to introduce something new for 2020 to test also for '21."