Following months of speculation, it would appear that Prodrive's F1 entry in 2008 is in serious doubt.

The British company was given the coveted "twelfth entry" last year, even though there were other existing teams with a (seemingly) better infrastructure already in place. Nonetheless, Prodrive got the nod with the David Richards' owned outfit planning to make full use of the new 'customer cars' rule and enter the 2008 championship with a McLaren-Mercedes package.

Doubt over the British team's entry first arose when the team postponed a planned announcement, then subsequently delayed yet again.

Now, the team has admitted that talks with McLaren have broken down, thereby leaving its entry in jeopardy.

"We cannot do the plan that we had with McLaren now," Richards told Reuters today. "There will not be a full-blooded equal car arrangement from day one, it cannot be," he added, though he didn't rule out the possibility of using a chassis provided by a rival team.

Although the team appeared to be close to reaching a deal, amongst other things, Williams has thrown a spanner in the works by issuing a legal challenge, which will be heard by the FIA's International Court of Appeal following the Brazilian GP.

From 2008, 'customer cars', whereby teams can purchase 'chassis and engine packages' from rivals will become legal, however, this is dependent on the teams signing a new Concorde Agreement, which hasn't yet happened. If the new Concorde Agreement isn't signed, the current agreement would continue, which would mean customer cars remain illegal.

Furthermore, there is every likelihood that Williams, which as Pitpass reported earlier today posted a £28m loss in 2006, could pursue its case in the civil courts, the British team arguing that teams which do not design and build their own cars should not be allowed to score championship points or share the constructors' financial pot.

"The Concorde Agreement is an agreement in law," said Patrick Head last weekend, "it covers commercial matters which the FIA have been told by the European Commission that they are not supposed to be involved with. They have been told they must not interfere in commercial matters.

"Obviously if a team comes into Formula One without any investment in the staffing and equipment that we've built up over the last 25 years and gains access to a (customer) car, then its a serious commercial threat to us," he added.

Of course, Super Aguri and Toro Rosso could also be affected since they use Honda and Red Bull packages, respectively.

In a brief statement Prodrive said they remained confident "that the short term issue of eligibility to race in 2008 will be resolved in our favour, it still leaves the question of longer term stability unanswered. It is Prodrive's opinion that the financial viability of a new team will not be possible until agreement is reached on a revised Concorde Agreement."

"Prodrive remains committed to participating in Formula One," Richards told Reuters. "We are hopeful that the current dispute over our eligibility to race will be clarified at the hearing later this month and that a Concorde Agreement between the FIA, FOM and all 12 teams can be established in the near future. In the meantime, we will consider all our alternative options for next season."