The first job losses to be announced by new Cadbury owner Kraft Foods will see its factory near Bristol closed by 2011.
The US-based firm, which agreed a deal to take over the Bournville giant last week, said following extensive talks with senior management at Cadbury, it had accepted plans to close the Somerdale manufacturing facility.
The decision was slammed by union representatives.
It means up to 400 jobs are set to be axed, amid plans to switch production to Poland, by the end of the year.
Kraft said that the previous Cadbury regime’s plans to close the site were too far down the line to be overturned.
The company said: “It has now become clear that the investment required to reverse the closure programme would be so significant that alternative plans were not viable.
"Cadbury has already invested more than £100 million in building new production facilities in Poland and the majority of the lines have, or are about to be, transferred by mid of this year.”
Kraft Foods chief executive Irene Rosenfeld added: “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.”
She continued: “We remain committed to investing in growing our combined business in the UK and will continue to support Cadbury’s existing £30 million investment plans for the Bournville site.
"During the next six months we are conducting a strategic review of our combined manufacturing network. We continue to believe that the combination of Kraft Foods and Cadbury will accelerate growth to the long term benefit of our employees.”
The company has said that it will honour Cadbury’s previous undertakings to Somerdale employees concerning the terms and conditions of the closure and the commitment to rebuild the Fry Club on the Somerdale site.
The announcement of the factory closure was slammed by Unite. Jennie Formby, the union's national officer for the food and drinks sector, said: "It is with great anger that we heard today’s announcement by Kraft that the closure of the Somerdale plant will go ahead as planned.
"Anger that Kraft deliberately misled many hundreds of decent men and women in Keynsham by saying that they would keep Somerdale open, despite Unite making very clear to them as early as September that this seemed impossible with the timeline for closure already seemingly set in stone.
"Anger that Kraft's thirst for public approval during the most unpopular takeover we’ve seen in recent times drove the company to ignore those warnings and instead choose to state repeatedly that the site would not close.
"Anger that they have ignored repeated requests for meetings and discussions over the future, and anger that even as senior management were on site in Somerdale preparing to make their statement to our members, a Kraft director was assuring Unite that they had not made any decision yet but we would be the first to know.
"This sends the worst possible message to the 6,000 other Cadbury workers in the UK and Ireland. It tells them that Kraft care little for their workers and have contempt for the trade union that represents them."