F1's teams have been warned they risk penalties if personnel visit the stewards at a race in future without being invited.
FIA race director Michael Masi wrote to all 10 teams in the wake of Sunday's British GP to clarify that visiting the stewards, who decide on incidents on the track and determine any penalties, will only be allowed by prior approval or official summons.
Mercedes boss Toto Wolff and Red Bull counterpart Christian Horner both visited the stewards' room during the red-flag period at Silverstone after Lewis Hamilton and Max Verstappen collided on the opening lap. The incident was under investigation at the time.
Both sides had already made representations over the radio to Masi. Horner blamed Hamilton for the incident before Wolff, defending his driver, had his say. During his dialogue with the latter, it was Masi who suggested that Wolff go and see the stewards.
"Michael, I just sent you an email with the diagrams where the car should be. Did you receive that?" Wolff asked Masi, to which the Australian replied: "Toto, I don't access my emails during a race deliberately because I'm concentrating on the race."
Wolff added: "You maybe should look at this because there is something with the rules. I am coming up."
Masi replied: "Feel free to go upstairs and see the stewards directly."
Horner soon followed to state Red Bull's case but said afterwards: "I don't think the stewards should be interfered with."
Communication between teams' pit walls and Masi is being played out on the TV world feed for the first time this season.
Writing in his post-race column, Sky Sports F1's Martin Brundle said: "It was a little uncomfortable hearing the Red Bull and Mercedes team managers and team principals endeavouring to influence the situation by lobbying the race director but that seems to be the communication system in place, and which we are broadcasting for first time this season.
"Michael Masi, the race director, quite rightly pointed them towards the stewards, and I can imagine a future revision on this process."