Formula One's governing body warned on Thursday that the sport is "becoming unsustainable" and invited teams to come up with new rules to slash costs and halve fuel consumption by 2015.
"The major manufacturers are currently employing up to 1,000 people to put two cars on the [starting] grid," International Automobile Federation (FIA) president Max Mosley wrote in a letter to the 10 teams at the British Grand Prix.
"This is clearly unacceptable at a time when all these companies are facing difficult market conditions.
"Also, with attention on energy problems worldwide, Formula One cannot afford to be profligate in its use of fuel," added the Briton.
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, said some major sponsors might already have left the sport without energy-saving initiatives already in the pipeline.
He said there is a need to at least halve the costs of manufacturer teams and, with Super Aguri already folding this year, ensure independents are financially viable without affecting the spectacle.
With the price of oil soaring to record levels on world markets against a backdrop of increasing economic gloom, Mosley invited the teams to make proposals that should aim to extract more useful energy from less fuel.
Despite efforts to present greener credentials, including the use of at least 5.75 percent bio-fuel from this season, Formula One remains for many the epitome of gas-guzzling wastefulness.
The rasping 2.4 litre V8 engines can burn close to a litre of fossil fuel per kilometre.
"The target should be a [very challenging] 50 percent reduction from today's levels of fuel consumption by 2015, while maintaining current speeds," wrote Mosley.
"The rules should encourage manufacturer teams to research technologies which are road-relevant rather than Formula One specific."
Mosley said the matter is urgent, with the teams' proposals needing to be ready within three months and the FIA prepared to step in and prepare new rules for 2011 if a majority of the teams did not show agreement.
In a more detailed look at the future rules, the FIA suggested the sport should aim to reduce fuel consumption by 20 percent for 2011.
It said this could be best achieved by placing a limit on fuel flow and the quantity of fuel used during a race.
