Sebastian Vettel took aim at Max Verstappen after the Red Bull driver suggested Ferrari's recent speed advantage has been gained by cheating.
Ferrari endured a struggle at the United States GP, Vettel retiring early in the race and Charles Leclerc struggling to keep pace with the top three, using an old spec power unit.
The performance came after a week in which the FIA had issued a Technical Directive to teams – prompted by a fuel flow proposal from Red Bull which was ruled illegal and seen as an attempt to get to the bottom of Ferrari's greater power.
In response to Ferrari's disappointing form in Austin, Verstappen said: "That's what happens when you stop cheating."
Vettel responded ahead of the Brazilian GP: "It is a sign of our times that a lot of people have something to say. I think the big difference to the past is a lot of people are being heard, whereas maybe before they were being ignored.
"Everybody is free to say what they want if that's what he thinks, that's what he might think. But obviously we have a different opinion.
"Should we have the strongest engine - I don't know the other manufacturers' power figures - that's a great achievement by us, by our engine department. For the last five years, we had Mercedes having the strongest engine.
"But since now for a couple of months we are ahead, then hopefully it stays like that for the next five years and I don't care what people think or say.
"I don't think anybody in the team took it personally. I think it's not professional and not mature.
"I don't have much interest in that, other than saying that for us, the best way to answer in a way is to probably go back to normal.
"We are not proud of how we performed in Austin on Sunday. After Saturday, nobody had the need to complain. On Sunday, I think we struggled probably with more than one thing, conditions, tyres, setup, which are things we need to work on.
"Calling it that far [cheating] I think is not right. But again, live and let live. If that's what he thinks, that's what he thinks. If next week he thinks something different, then, in the end, we don't care so much."