Britvic has confirmed it is to close its factory in Norwich, leading to the loss of more than 200 jobs.
The drinks manufacturer, which makes Robinsons and Fruit Shoot, will transfer production to its other sites in the UK by 2019.
In a statement, Britvic said it would offer every employee support and redeployment opportunities.
Robinsons has been based at the Carrow Works site since 1925 and 249 people are currently employed by Britvic in Norwich.
“This was not a proposal that we made lightly and we understand that the outcome of the collective consultation process will be upsetting for our colleagues in Norwich," Britvic Chief Executive Simon Litherland said.
"It is a sad and difficult time. I want to thank everyone at Norwich, past and present, for their dedication, hard work and commitment, and I would like to say again that this decision is in no way a reflection of their performance.
"However, transferring production of Robinsons and Fruit Shoot to our other GB manufacturing sites – coupled with our investment in the wider GB supply chain - will deliver significant productivity and efficiency savings in our manufacturing operations.
"It will also deliver environmental benefits and ensure that we have the flexibility and capability we need to respond to changing consumer trends faster and more efficiently.”
The closure, which was first proposed in October, raises further questions over the future of Unilever's Colman's factory at the same site which it shares with Britvic.
The Norwich South MP Clive Lewis has called the decision a "real kick in the teeth" for the city.
"I am so, so sorry for all the Britvic employees and families who’ve just got the news that Britvic have decided to leave our city," he said in a statement on his Facebook page.
"It’s a real kick in the teeth to the city of Norwich. The workers there will have felt that Britvic went into this process knowing full well which way it was going with this.
"It’s a real body blow for staff who have worked so hard and they have every right to feel hard done by. It’s an awful time of year for this to happen and they have to go back to their families knowing the company is leaving.
"There are of course knock-on effects for Colman’s too, which remain to be seen. This city and generations of families have contributed to making the brand what it is.
"I know that at least one trade union for the site is deeply unhappy with the way that the consultation preceding closure was conducted. I am working with that union to try and get some kind of more positive outcome from all of this for employees."