Tata Motors, the car arm of the Indian conglomerate, should finally complete a $2bn (£1bn) deal for Land Rover and Jaguar on Wednesday.
Ford, the owner of the West Midlands-based luxury brands, has been in talks with preferred bidder Tata since December, but negotiations have been protracted due to union concerns over the future of more than 15,000 jobs. Tata is also believed to have sought guarantees from Ford over supplies of vital components such as engines.
There was talk of Ford retaining a stake in Jaguar Land Rover, as the US car maker did when it sold Aston Martin to a consortium led by David Richards, the automotive entrepreneur, for $848m last year.
However, a source said: "Since Ford will be a supplier, retaining a stake could have led to a conflict of interest."
Tata has agreed to continue with Ford's current business plan, which runs to the end of 2011, quelling union fears of immediate job losses.
Ford has owned Jaguar since 1989 and bought Land Rover in 2000. They were put up for sale last summer.
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