Mosley is keen to reduce costs and fuel consumption in F1 in the coming years
World motorsport boss Max Mosley has warned that Formula One is becoming "unsustainable" and urged teams to find ways to cut costs and fuel consumption.
FIA president Mosley says "tough market conditions" mean F1 must cut costs by 50% and improve fuel efficiency.
He invited teams to tender proposals "that we can turn into detailed rules.
And he added: "These must be ready by 3 October and have the support of the majority of teams. If not, the FIA will prepare new rules for 2011 itself."
A detailed breakdown of the fuel-saving proposal targeted a 20% reduction in fuel consumption by 2011, "progressing to 50% in 2015".
At present, the fuel consumption rate of Formula One cars is around four miles to the gallon, but Mosley - who won a confidence vote last month to stay in office after a sado-masochistic sex scandal that his critics say has damaged Formula One - insists that must change.
The issues are outlined in a letter submitted to the 10 team principals ahead of this weekend's British Grand Prix at Silverstone.
"Formula One is becoming unsustainable," reads Mosley's letter. "The major manufacturers are currently employing up to 1,000 people to put two cars on the grid. This is clearly unacceptable at a time when all these companies are facing tough market conditions.
"Also, with attention on problems worldwide, Formula One cannot afford to be profligate with its use of fuel."
The FIA has already set out part of its green initiative with the planned phased introduction of the Kinetic Energy Recovery System (KERS), which will channel energy generated under braking into batteries that can then be used to power the cars.
And Mosley's letter indicates fuel consumption could best be reduced by placing a limit on fuel flow and the quantity of fuel used during a race.
F1 boss Bernie Ecclestone, who has been in dispute with Mosley over the future direction of the sport, backed the proposals.
The 77-year-old told the Times he was pleased Mosley had conceded one of his wishes, that the teams are more involved in the writing of the regulations.
"I am happy that the FIA has taken the initiative to allow the teams to write the regulations," Ecclestone said.
"They will be able to control their expenditure. What Max put in the letter is correct - it's a little cranky that it takes 1,000 people to put two cars on the grid."
Ecclestone's dispute with Mosley has centred on trying to secure a new Concorde Agreement, the document by which the sport was governed from 1981 until it lapsed at the end of last year.
Mosley has so far refused to sign a new Concorde Agreement, which has left the FIA with absolute power over the new rules.
It is not clear whether a new Concorde Agreement is any closer, but Ecclestone did say he and Mosley, a friend and associate of nearly 40 years, had reached a rapprochement.
"The bottom line is simple - we have moved to patch up our differences," Ecclestone said.