Food giant Kraft today signalled the loss of up to 400 jobs by announcing the closure of a Cadbury factory - despite earlier promises to keep it open.
The US firm said it was "unrealistic" to reverse Cadbury's plans to shut the site at Somerdale near Bristol and announced that the factory would shut by 2011.
Kraft, whose five-month battle for control of the confectioner was sealed earlier this month, had pledged to retain the plant.
But today it said Cadbury had already spent £100 million on building new facilities in Poland and most production would be transferred by the middle of this year.
Kraft said last week it would keep the Somerdale factory open but today chairman and chief executive Irene Rosenfeld said: "In our recent talks with Cadbury senior management, it became clear that it is unrealistic to reverse the closure programme, despite our original intent to do so.
"While this is a difficult decision, we have moved quickly to end any further uncertainty."
Union Unite reacted with anger to the decision and said it sent the "worst possible message" to 6,000 other Cadbury workers in the UK and Ireland.
Jennie Formby, Unite national officer for the food and drinks sector, said the US firm had "deliberately misled many hundreds of decent men and women" at the site by promising to keep the factory open despite union concerns that this looked impossible.
She added Kraft's "thirst for public approval during the most unpopular takeover we've seen in recent times" led the company to ignore those warnings.
Business Secretary Lord Mandelson met Ms Rosenfeld after the takeover was sealed but failed to win a specific commitment on jobs.
Cadbury announced in 2007 that it planned to close Somerdale and transfer the work done there to Poland with the loss of about 500 jobs.
About 100 workers have already been made redundant but Kraft's ownership had offered hope that the remaining jobs could be saved.
Hundreds of Cadbury workers staged a noisy protest in Westminster last week over the takeover and call on the Government to do more to protect their jobs.
Today Ms Rosenfeld said the firm remained committed to investing in the combined business in the UK and would continue to support Cadbury's £30 million investment plans for its Bournville site.
"During the next six months we are conducting a strategic review of our combined manufacturing network," she said.
"We continue to believe that the combination of Kraft Foods and Cadbury will accelerate growth to the long term benefit of our employees."
Kraft said it would honour Somerdale employees' terms and conditions of the closure undertaken by Cadbury and the commitment to rebuild the Fry Club on the site.
The Somerdale plant is in Keynsham near Bristol and Bath, and was originally built by the Fry family.
After the First World War, Cadbury Brothers merged with Fry & Sons in 1919, leading to the relocation of production from sites in Bristol.
The transfer of production was completed in 1935, and at its height the Somerdale workforce was more than 5,000. It had its own power station and railway, with connection to the Great Western Railway via sidings at Keynsham station.
The factory was built with social facilities, including playing fields and a large recreational sports grounds, which still serve Keynsham.
Products manufactured at Somerdale include Fry's Chocolate Cream, the Double Decker, Dairy Milk, Chocolate Buttons, Creme Eggs and Mini Eggs, Cadbury's Fudge, Chomp and the Crunchie.