Colman's Mustard production will begin to leave its Norfolk factory within six months as part of a 'phased transfer of production' by owner Unilever.
The consumer goods group revealed the process would begin this autumn and be completed by the end of 2019 as it announced the end of the first phase of consultation with Norwich workers.
The announcement confirms proposals made at the start of January – that Colman's 160 year association with the Carrow Works site would come to an end.
READ: Mint and mustard growers will preserve historic supply lines to Colman's in Norwich
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It means 113 jobs in Norwich are at risk of redundancy with 40 roles transferring to Burton and 25 jobs expected to be created at a new milling facility in the 'Norwich area'.
The company has not yet confirmed where the milling site, which it has said it will invest 'millions' in, will be based but has previously sad the proposed food hub near Easton was being considered.
The Colman's factory shared a site with Britvic which announced it was to close its production facility in December having proposed plans in October.
Jon Strachan, vice-president of supply chain at Unilever UK & Ireland, said: 'We have confirmed today that our Norwich factory will close at the end of 2019. This follows Britvic's decision last year that it will close its factory on our shared site.
'We appreciate this is very difficult news for our employees and their families, and we would like to thank everyone for their commitment and contribution to our business over many years in Norwich.
'The proposals we are now moving forward with represent the best long-term solution for Colman's production in the UK, whilst preserving the historic link with Norwich.
'We believe in doing the right thing for our people and are committed to treating them with fairness and respect. We will be offering employees who are affected a comprehensive package of support, including discussing redeployment opportunities at other sites and providing services to help people find new employment.'
Ivan Mercer, regional officer for the GMB union, said many members at Unilever in Norwich felt the decision to close the factory was 'predetermined'.
'The Colman's site is hugely profitable, but the company have been prepared to sacrifice the Colman's legacy purely for greater margins,' he said.
'For the Norwich community the combined closure of both Britvic/Robinsons and Colman's will result in nearly 1,000 direct and indirect job losses, and nearly £10m of wages sucked out of the local economy.
'It is a devastating blow to the legacy of UK manufacturing and the silence from the government to date has been deafening.'
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