Lotus is close to finalising a switch to Renault engines for next season - but the deal still hinges on whether it can find an agreement with Cosworth to end its contract with the famous engine-maker two years early.
AUTOSPORT understands that a deal has been agreed in principle for Lotus to secure a supply of Renault customer engines for 2011 - which would see the team receive the same specification of power-unit as other customer outfit Red Bull Racing.
It is believed the move came out when Lotus originally sought out a new supplier of gearboxes and transmissions for next year - after frustrations with reliability in that area throughout the course of this season.
Renault was more than happy to supply its gearbox and transmission units but, on the back of a push to increase its engine supply deals, it made a big effort to sell its power unit as part of the package too.
However, despite sources suggesting that a deal is ready to be signed for Lotus and Renault to tie up for the first time since 1986, the Hingham-based outfit still needs to resolve contractual issues with Cosworth.
As part of the deal it made when it entered F1 this year, Lotus signed a fixed three-year contract with Cosworth - and it is believed there is no break clause that would allow the team to get out of that unless the Northampton-based engine supplier was willing to do so.
It is not clear at the moment whether a financial settlement can be reached for Cosworth to agree to cut short its deal, or whether Lotus will be forced to delay its Renault ambitions.
Neither Lotus nor Cosworth have elaborated on the situation, and both insist that there are no plans for their relationship to change for now.
Cosworth general manager of F1 operations Mark Gallagher said: "As with the other new teams, Lotus has a fixed term three-year contract with Cosworth and we are very pleased it is happy with our engines and the job we have done for it during its first season in Formula 1."
Lotus technical chief Mike Gascoyne said: "We've got a contract with Cosworth and there is no further comment to make."
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