Red Bull boss Christian Horner has warned that the end of the engine development token system will lead to a spending war by the F1 manufacturers.
As part of the deal to cut customer supply prices - a move that will actually save Red Bull money – the FIA has agreed to abandon tokens from 2017.
The move means that there will be no restrictions on engine development after this season, something Horner admitted he was baffled about.
"What I don't understand is totally getting rid of all tokens and opening all development," said Horner. "Because that cannot be a healthy situation for the sport, to just encourage serial spending.
"I don't think that will breed a healthy competition.
"That needs to be addressed moving forward, and hopefully the regulators will come up with some clear rules to deal with that in due course."
Asked by Motorsport.com if he feared that Mercedes would make better use of the freedom than rivals, he said: "I don't think you could pinpoint one or the other, but if it just ends up in a spending frenzy is that a healthy situation?
"For example on the chassis we are very tightly governed in terms of the amount of wind tunnel we can use, the amount of simulation we can use for CFD.
"To be able to do as much running with as many engines on as many dynos and as much development as you like, it doesn't seem a sensible solution."