Christian Horner lashed out at fellow team boss Zak Brown for leveling cheating allegations at Red Bull in a recent letter sent by McLaren to the FIA.
Brown's missive to F1's governing body clarified McLaren's position on cost cap breaches, and stated that any overspend by a team identified during the FIA's audit process would "constitute cheating" as far as McLaren was concerned and should warrant a severe financial and sporting penalty.
Red Bull has been found guilty by the FIA of a "minor" cost cap breach in 2021, meaning an overspend of maximum $7.5 million of the team's limited $145 million budget.
The FIA has not yet revealed the exact amount of Red Bull's overspend, nor offered any specifics regarding how it was achieved.
While McLaren did not name Red Bull in its letter to the FIA, it did reference a "team guilty of a minor overspend breach plus a procedural breach", stating that such a transgression was a clear case of cheating.
In a remake on Saturday at COTA of "Round-up at the OK Corral", Horner came out with all guns blazing as he sat next to a visibly uncomfortable Brown in the team principals' media conference.
"Zak’s letter, which wasn’t copied to us – we’ve had sight of that letter and it’s tremendously disappointing for a fellow competitor to be accusing you of cheating," Horner said.
"To accuse you of fraudulent activity is shocking. It’s absolutely shocking that another competitor, without the facts or any knowledge of the details, can be making that kind of accusation.
"We’ve been on trial because of public accusations since Singapore. The rhetoric of ‘cheats’, that we’ve had this enormous benefit.
"The numbers that have been put out in the media are miles out of reality. The damage that does to the brand, to our partners, to our drivers, to our workforce."
Hamilton: F1 cost cap useless if breaches get 'slap on the wrist'
Horner indeed claimed that McLaren's "fictitious allegations" leveled at Red Bull had led to members of the team and their children being bullied.
"In an age where mental health is prevalent, we’re seeing significant issues within our workforce, we’re getting kids that are being bullied in playgrounds who are employees’ children," Horner explained.
"That is not right. Through fictitious allegations from other teams. You cannot go around making that kind of allegation without any fact or substance.
"So, we absolutely are appalled at the behaviour of some of our competitors."
Red Bull is currently in talks with the FIA over a proposed Accepted Breach Agreement that, according to reports, would include a financial penalty as well as a sporting sanction, with the team being hit with a reduction of wind tunnel time for 2023.
But it is believed that Red Bull is still contesting the FIA's interpretation of its cost cap submission.
In response to Horner's scathing attack, Brown took the stand and said: "My letter set out that if someone, a team, spends more than the cap, they’re going to get an advantage.
"The cap is a rule, no different to the technical rules in the sport. We’re not taking a view on whether they did or didn’t.
"[The idea was] ‘If someone has, here are the things that should be addressed’, no different than if a ride height is incorrect or a flexi-wing or whatever the case may be.
"I didn’t mention any teams, it was a general response. Now that we’re into the cost cap era, if someone breaches that, here’s what we think some of the ramifications are.
"I have no idea what the number is, I know none of the detail. If we had more money to spend, that would put us in a better light and performance – more people, more upgrades, whatever the case may be.
"We feel it’s a performance benefit if someone has spend more than the allocated cost cap. That is up to the FIA whether to determine whether they have or haven’t."
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