McLaren Racing Director Eric Boullier believes Red Bull used coded radio messages during the Singapore Grand Prix.
The FIA announced a major clampdown on radio transmissions that help with car or driver performance ahead of the race weekend at the Marina Bay Street Circuit.
However, some of the restrictions were relaxed before FP1 on Friday but coaching in terms of where the driver was losing time, where to brake and how to corner quicker, among other things, remained banned.
Teams tried to best to avoid giving advice on Sunday, but Red Bull at one stage told Daniel Ricciardo, who had a problem with his battery, that “avoiding exit kerbs may help the problem with the car”.
Boullier was not impressed and felt the Milton Keynes squad broke the new rules.
“We had no issues (with the new radio rules) on our side,” he is quoted as saying by Press Association Sport. “It just made us more busy listening to others to make sure they made no mistakes, like Red Bull twice with Ricciardo.
“I think it was coded, but it is up to the FIA to investigate. It is not for me to investigate.
“But it was a strange message. Once was okay, but twice, three times? You can doubt what exactly the car problem was.”
However, Red Bull confirmed via Twitter that they were given the all clear by race control.
“The FIA has confirmed to the Team that it’s satisfied the messages were related to car reliability concerns, so no coded messages,” it read.