By Andrew Benson Motorsport editor at the Hungaroring

Jordan and Stoddart joined forces ahead of the Hungarian GP

The owners of the struggling Jordan and Minardi teams have criticised their Formula One rivals for failing to agree on a set of new rules for next season.

Eddie Jordan said it was "preposterous" not to know the restrictions to which they would be designing their cars.

Ferrari technical director Ross Brawn said that there was broad agreement on changes to the cars and tyres, but that the engine rules needed to be decided.

But Minardi's Paul Stoddart said the team owners were "nowhere near" a deal.

The row came in a bad-tempered news conference at the Hungarian Grand Prix on Friday.

Stoddart and Jordan rounded on the designers and their fellow team owners for not yet agreeing on the 2005 rules.

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Stoddart said that, unlike the top teams, Minardi could not afford to run parallel development programmes designing different cars while waiting for a definitive set of rules.

Jordan said: "We need certainty and we need it immediately.

"It is preposterous that a clear set of rules and regulations for next year's championship are not clear and settled by now."

But Brawn said F1's Technical Working Group had agreed on a set of rules that would "by default" become the 2005 regulations.

"I'm surprised Eddie doesn't know that we have a set of regulations, because as far as we [the chassis designers] are concerned they are virtually agreed," he said.

Brawn claims agreement is not too far away

"The tyre regulations are in place because Bridgestone and Michelin have written to the FIA [the sport's governing body] with a proposal that the FIA has accepted.

"The only debate is over the engine."

Brawn said that the level of aerodynamic downforce would be reduced by reducing the height of the diffusers that channel air out of the back of the cars, raising the height of the front wings and moving the rear wings forward.

A single set of tyres would have to last the entire race, said Brawn, adding that the "only debate" was over the engine.

There is a proposal to make engines last for two race weekends to reduce power as an interim step towards replacing the current three-litre V10s with 2.4-litre V8s in 2006.

But Stoddart said: "The team principals are nowhere near agreeing the two-race engines.

We have an engine manufacturer saying they are going to pull out if that is implemented and a team owner saying that, too."

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There is also no agreement on the format of qualifying, which has been widely criticised in its current form.

McLaren team owner Ron Dennis is the biggest opponent of the changes, sources have told BBC Sport.

Jaguar boss Tony Purnell said: "Having sat in team owners meetings, the Byzantine nature of F1 politics can mean that surprises happen. But having said that Ross is the probable clairvoyant here."