The first question posed over the threat of a breakaway race series was answered immediately for the eight rebel teams within hours of their announcement that they were walking out of Formula One.

Sceptics claimed they would have nowhere to race if they left the official series administered by the FIA, under president Max Mosley.

But Silverstone quickly emerged as a potential venue after executives said they would listen to proposals to run an alternative race after losing the contract for the British Grand Prix to Donington from next year.

As they opened the door to the rebels, it became increasingly clear that other circuits around the world dropped by Bernie Ecclestone, Formula One's impresario, would step into the breach if the "breakaway eight" needed somewhere to race.

Robert Brooks, chairman of the British Racing Drivers' Club, who own Silverstone, said: "We would have to listen to proposals. Clearly, we do not have a grand prix next year and we will have a slot so it is something we would have to consider."

Formula One has fled its traditional heartland in Europe for exotic new tracks in the Far East under Ecclestone's direction, leaving a trail of circuits in its wake. Few would turn away the chance to host a race under new management featuring the greatest names in motoring racing, led by Ferrari and McLaren Mercedes.

Tracks such as Imola in Italy, Magny Cours in France, Jerez in Spain, as well as Silverstone would happily welcome back the highest quality racing, while Hockenheim and the Nurburgring in Germany are currently sharing the German Grand Prix in alternate years, so one of those would also be free.

In addition, Suzuka in Japan, one of the most evocative circuits in the world, lost the Japanese race to Fuji while the United States remains wide open after Ecclestone failed to agree new terms there and the authorities in Montreal in Canada were aggrieved to lose their popular date in the calendar.

The biggest problem facing the breakaway would be the television rights already in the hands of Ecclestone and CVC Capital Partners, the company that owns Formula One's commercial rights. The new series would have to negotiate new deals rapidly, all the time hoping that existing broadcasters, such as the BBC, might also be willing to make the break with the Ecclestone establishment.

It is known that key broadcasters have clauses stipulating that the biggest players are on the track; Sky Italia, for example, is thought to have a clause that demands Ferrari is among the field and Ferrari is the biggest draw by far. Any series with Ferrari is almost bound to succeed, particularly backed up by Lewis Hamilton's McLaren Mercedes squad and Brawn GP, led by Jenson Button, a potential world champion this season.

Meanwhile, sponsors are frantically trying to get answers to what is happening and what it means for them. Some - such as Santander, Vodafone and Marlboro - are paying tens of millions of pounds into a sport they have no guarantees will exist beyond the end of this year. Phone lines to Silverstone were hot throughout Friday as sponsors and figures in the City with financial stakes in Formula One tried to ascertain just how lethal the threat is.

Ross Brawn, owner of the world championship-leading Brawn GP team, arrived at Silverstone saying that he still hoped for compromise. But that seems unlikely without a shift in positions on both sides of seismic proportions.