The 126-year-old plant at Leamington Spa, will close in July after the company decided it had become too uncompetitive.
Workers will be offered early retirement, voluntary redundancy or redeployment and there will be no compulsory lay-offs, said Ford president John Fleming.
He revealed that the plant, which Ford bought in 1940, is making losses of around £10 million a year.
"Ford workers in Leamington are being effectively bribed with enhanced payments to accept the closure of a plant which is one of the most productive in Europe," said Dave Osborne, T&G national secretary for the car industry.
"The T&G does not accept this closure as either inevitable or non-negotiable and we’ll do all we can to reverse the decision," he added. Osborne said it appeared the failure of Ford to put new work on the Fiesta to the Leamington plant may have been a factor in today’s announcement. He also warned that Ford was looking to join the manufacturing march to the east and said that was another reason to make it clear the union’s opposition to the closure.