Toro Rosso team principal Franz Tost believes Formula 1 bosses should freeze Mercedes’ engine development so its rivals can catch up.
Since the turn of the V6 hybrid turbo era in 2014, Mercedes has won 51 out of the 59 races that have taken place since the Australian Grand Prix of that year.
Other rivals have since struggled to make gains on the development rate Mercedes have put into its project, however, it is believed Ferrari has been the closest in terms of power output.
For 2017, the manufacturers and the FIA have made agreements on certain parts of units which cannot be developed throughout the year, these include crankshaft diameters and the minimum weights of the MGU-H and MGU-K.
Tost told Autosport: “I hope that earlier or later there will be a power unit parity because this is not the case currently.
“We need Red Bull, Mercedes and Ferrari fighting for the championship at least.
“If the power unit parity is not coming then the FIA should come up with a regulation to freeze it. I would freeze the power unit from Mercedes, the others should catch up and then they freeze all of them.
“I would leave the development of the battery free because the battery is something for the future and it is also something important for the manufacturers.”
Tost is also of the belief that cost caps should be in place, rubbishing claims that it can’t be enforced.
“We have to come down with costs,” Tost added.
“We have discussed this for years now but nothing happens.
“I would come in with a cost cap. People say it’s not controllable but that’s nonsense.
“At Toro Rosso we have a history about every screw and we can tell you where it’s coming from and how much it costs.”
