Formula One's governing body has agreed to exclude drivers' salaries and marketing costs from an optional budget cap to be introduced for teams next season.
FIA president Max Mosley has also written to teams asking them to advise him by today whether the 30 million pound or about 80 million dollar cap should be revised.
He's warned that the sport, which saw Honda depart in December, risked losing at least two more teams for 2010 were the cap not to be an option.
Those accepting the budget cap will have greater technical freedom than teams who prefer to continue with unlimited budgets, theoretically allowing them to be competitive with less money.
Several parties, including Lola and former Benetton and BAR boss David Richards, have expressed interest in entering under such a cost cap and Mosley said the FIA would select three.
The cost cap option was put forward as part of measure to cut costs and protect the sport from the ravages of the global credit crunch.