FIA race director Michael Masi has reportedly told competitors that F1 team personnel will no longer be granted access to the stewards' office during deliberations without prior approval.
Last weekend's controversial incident in the British Grand Prix between Max Verstappen and Lewis Hamilton sparked a series of exchanges between the Red Bull and Mercedes' pitwalls and Masi as each team argued its case.
But the tension ramped up a notch when Mercedes boss Toto Wolff offered to visit the stewards as they were investigating the clash between the two championship contenders, an initiative that Masi welcomed.
"I think I was told after the accident that Christian, in particular, had a pretty erratic discussion with the race director," said Wolff, speaking to Motorsport.com.
"So I contacted the race director and he advised me to go to the stewards, or to speak to the stewards directly, which I did."
However, upon hearing of Wolff's intention to lobby the officials, an angry Christian Horner followed suit and joined Wolff in the stewards' office.
"I went to see the stewards because I'd heard that Toto was up there, presenting a case," explained Horner after last Sunday's race.
"You want it to be fair and balanced, and I don't think anybody should be allowed to see the stewards.
"They should be locked away so they’re not influenced and for me that was unacceptable that he had gone up there to lobby the stewards."
Masi initially stated that he had no problem with senior team members visiting the stewards judging a case. But the Aussie has apparently changed his stance on the matter according to a report from Motorsport.com.
F1's race director has allegedly sent a note to competitors clarifying that in the future access to the stewards' office for team personnel will be contingent on a "prior approval" or as the result of a summons.
Masi has also warned teams that any breach of the latest guidelines could result in a sanction under Article 12.2.1.i of the FIA's International Sporting Code, which sanctions ranging from a simple reprimand to a disqualification.