Red Bull and sister team Toro Rosso were reportedly the only teams not to sign the letter.

"The teams asked the FIA to continue the process of looking at cost control," Mercedes team principal Ross Brawn said. "It's something which the FIA are very keen to do as well, so it was a letter of support to the FIA to say that we want to continue the process of reducing costs and look at fair ways of introducing the regulations or procedures to keep the costs under control and further reduce the costs."

"I read a few days ago that Mr. Ecclestone was commenting that we should introduce budget cuts into Formula One, so you could say that there's quite a consensus now about doing something further," Williams team principal Adam Parr said.

"How much money a team spends should be down to the individual team," Red Bull team principal Christian Horner told Autosport magazine last month. "It shouldn't necessarily be that a team gains an advantage by doing that.

"Once you get into equivalence, structures of companies are different and that is where it becomes murkier."