Eight Formula One teams have accused Ferrari of acting against the interests of the sport by testing at will.
Ferrari have angered their rivals by continuing unlimited testing
All nine teams had agreed to limits on testing to cut costs, only to have their plans dismissed by Ferrari.
The Italian team, who own two private test tracks, are unwilling to place restrictions on testing their cars.
In a statement issued on Friday, the teams claim Ferrari's actions will "potentially destabilise" the sport and give the champions an unfair advantage.
The statement initially claimed that Sauber, who use Ferrari engines, was included, but they broke ranks on Saturday, saying the unsigned document had been issued "without the prior approval of some of the aforementioned teams".
None of Ferrari's rivals enjoy the same facilities and they had agreed to limit testing to 30 days over the season.
The statement, issued by Minardi on behalf of Ferrari's nine championship rivals, read: "Ferrari's actions not only potentially destabilise Formula One and increase costs, but also provide Ferrari with an unequal advantage over all the other teams.
"Inevitably, such action on the part of Ferrari can only increase costs within Formula One and undermine the principle of a level playing field in the sport.
"The nine teams are requesting that Ferrari now reconsiders its position and acts in a responsible manner to support this valuable cost-saving initiative."
In response, Ferrari have argued that testing restrictions will benefit their rivals, as Michelin have seven teams testing their tyres, whereas Bridgestone rely on Ferrari.
Ferrari boss Jean Todt said: "Ferrari are the only team moving Bridgestone's tyre development forward, which also benefits Jordan and Minardi (who also use Bridgestone).
"Also the current test programme is more efficient in terms of the use of manpower and resources.
"It will lead to a reduction in our costs, currently estimated at £1.4m."
Ferrari technical director Ross Brawn added: "We wanted to find a solution and we don't want to be at odds with our fellow teams.
McLaren use De la Rosa to gain extended mileage on Fridays
"We tried to offer some compromises but they weren't acceptable to the other teams and their compromises were not acceptable to us. It's an unfortunate situation."
Brawn has also criticised the rule that allows top teams like McLaren to run a third car in Friday practice at Grands Prix after they finished fifth in the championship last year.
"I think it's a gross anomaly. It was intended to give some commercial benefit to the less well-off teams to enable them to sell a third car for a Friday.
"To have a team of the calibre of McLaren, or last year BAR, having the benefit of a third car on a Friday is a nonsense. And I don't agree with it."