Formula One bosses appear poised to have to fend off another controversy ahead of this weekend's German Grand Prix, amid claims that they 'hand-picked' newcomers for the 2010 championship based on their willingness to use Cosworth engines.

According to reports in the Daily Telegraph's business section over the weekend, the FIA stands accused of 'commercial bias' in its decision to offer entries to US F1, Campos Grand Prix and Manor F1 - who are scheduled to join the existing ten teams on the grid next season - ahead of more established names such as Prodrive/Aston Martin and Lola, both of which were widely assumed to have been 'kept back' in order to exert extra leverage on the dissident FOTA teams in the battle for control between the teams organisation and FIA president Max Mosley.

The report claims that many of the twelve teams overlooked for a place in F1's new-look line-up have now revealed that they had been told that running engines from Cosworth - which won an FIA tender to supply a spec-engine to the category - was a 'mandatory condition' for selection by the governing body. Unaware of the requirement, the disgruntled teams submitted their bids with plans to use alternative power suppliers - with one believed to have spent ?1m preparing its bid.

"We were told that, if we wanted to take up the 2010 grid slot, we would have to sign a three-year engine contract with Cosworth," one team boss claimed, while another insisted that his outfit 'had a real possibility of obtaining a Renault, Mercedes or Ferrari engine'.

As Cosworth insisted that it did not put pressure on the FIA to impose such a condition on entry, a third team insisted that the newcomers had been 'hand-picked for political, rather than sport[ing] criteria', underlining suggestions that, with current engine suppliers BMW, Mercedes, Ferrari, Renault and Toyota all potentially involved in the proposed FOTA breakaway, the FIA needed to find an independent alternative that would render such a pressure scenario unlikely in future.

"The whole grid would be at the mercy of the car industry and no new team would be able to enter without their permission," an FIA spokesman confirmed.

US F1, Campos and Manor all came through the selection process designed to fill at least three places on the 2010 F1 grid after the FIA opened up extra grid slots in a bid to 'improve the show'. Although the potential of additional entries was closed by the peace accord hammered out between Mosley and FOTA, many of the teams missing out in the initial selection had revealed that they remained in conversation with the governing body should an opening become available.

Brawn GP CEO Nick Fry has also intimated that the 2010 grid is not yet set in stone, particularly as the three newcomers had all submitted their bids on the basis of the sport being subjected to a ?40m budget cap - an idea scrapped as part of the deal that brought the two warring factions together shortly after the British Grand Prix.