Bernie Ecclestone has told the Formula 1 drivers not to publicly criticise tyre supplier Pirelli.
Following Sebastian Vettel's angry rant after a blow-out cost him at the Belgian Grand Prix, Pirelli's tyres have grabbed the headlines.
But no more.
The drivers and teams met with Pirelli and Ecclestone in Monza on Friday at which time they were told to keep their comments in-house.
"If any one of them has got problems, they should talk to the people making the problems," said Ecclestone.
Pirelli motorsport director Paul Hembery confirmed the gagging order.
He said: "They've been asked to do it in the right environment, which is in the teams and with us.
"They should express their opinions in the right manner.
"Other things happen in the sport and they don't offer an opinion, so it just needs to be balanced."