Red Bull boss Christian Horner says his Formula One team is is "probably due an apology from some of our rivals" over the 2021 cost cap breach controversy.
The F1 team last week accepted a substantial fine and sporting penalty from governing body the FIA, after they were found to have breached the $US145 million ($A226 million) cost cap during the 2021 season.
Red Bull have agreed to pay the $US7 million ($A11 million) fine, as well as having their wind tunnel testing time slashed by 10 per cent for 2023.
Rumours of the cost cap drama started swirling during the weekend of the Singapore Grand Prix, with the FIA only confirming one week later at the Japanese GP that Red Bull were in breach of the rules.
Speaking after the Mexican GP when his Red Bull team accepted their punishment for the 2023 season, Horner said it was "hugely worrying" that details had leaked about the issue in Singapore before the FIA had even made its findings public.
McLaren boss Zak Brown was one of the more vocal critics, having insisted that any cap breach constituted "cheating".
The McLaren boss did not directly name Red Bull or Aston Martin, who were deemed to have committed a procedural breach, in the letter dated October 12 with copies sent to those other teams who complied with the financial regulations.
"The overspend breach, and possibly the procedural breaches, constitute cheating by offering a significant advantage across technical, sporting and financial regulations," Brown wrote.
"The bottom line is any team who has overspent has gained an unfair advantage both in the current and following year's car development.
"We don't feel a financial penalty alone would be a suitable penalty for an overspend breach or a serious procedural breach. There clearly needs to be a sporting penalty in these instances, as determined by the FIA."
Horner says the backlash his team copped was "upsetting" for all involved and called on the governing body to investigate the fact its cost cap breach was leaked.
"The accusations made in Singapore were extremely upsetting for every single member of staff, all our partners, everyone involved within Red Bull," said Horner.
"Obviously, any form of leakage is hugely worrying. It's something that we expect to be followed up."
Horner conceded that his team made mistakes when it came to the 2021 cap breach, but denied they were intentional.
Red Bull slams 'cheating' suggestions
"Potentially mistakes have been made in our submission, which with the benefit of hindsight and 20/20 vision, everybody can be a specialist.
"But there was no intent, there was nothing dishonest, and there was certainly no cheating involved which has been alleged in certain quarters. So I don't feel that we need to apologise.
"I think there are lessons that have been learned. Everybody can learn from this. We've taken our pounding in public, we've taken a very public pounding, through the accusations that have been made by other teams.
"Our drivers have been booed at circuits. And the reputational damage that has been made by allegations has been significant. The time has come for that to stop."
Horner said Red Bull's fine for the cap breach was a significant sum but admitted that "the more draconian part is the sporting penalty".
"Let me tell you now, that is an enormous amount," he said of the wind tunnel usage reduction.
"That represents anywhere between a quarter and half a second's worth of lap time.
"That comes in from now, that has a direct effect on next year's car and it will be in place for a 12-month period."
Horner said Red Bull, the team of double world champion Max Verstappen, were also "victims of our own success" with an additional reduction in wind tunnel use for winning the 2022 championship.
"We will have 15 per cent less wind tunnel time than the second-placed team in the constructors' championship and 20 per cent less than the third place," he said.
"So that 10 per cent put into reality will have impact on our ability to perform on track next year."
Horner said his team had accepted an agreement with the FIA because it was in the sport's interest to close the book on the matter rather than risk it rumbling on for months and potentially to an appeal court.
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