About 300 jobs are at risk at a Nottinghamshire food processing site earmarked for closure.
Workers at Welcome Foods at Huthwaite, near Sutton in Ashfield, were told the firm has been "impacted by difficult trading conditions".
The union Unite said the closure was a "heavy blow" for the workforce and the local economy.
Parent company Bakkavor has begun a consultation to move work to its other sites.
'Large-scale job losses'
Steve Syson, regional officer for the union, said: "The union wants an urgent meeting with the management next week, with the aim of mitigating and reducing the large-scale job losses.
"We want to explore the business reasons for the planned closure during a 45-day consultation period and the opportunities for alternative employment within the group."
In a statement, Welcome Foods, which makes sauces and gravy, said: "The group has explored a number of different options to sustain the business, but has now concluded Welcome Foods is no longer commercially viable.
"Therefore, our proposal is to cease operations at Welcome Foods and transfer production to other Bakkavor sites which have similar product synergies."
The company added that if the proposal goes ahead it would "make significant efforts" to find alternative jobs for workers locally or elsewhere within the Bakkavor group.
Bakkavor employs more than 18,000 people worldwide across 43 facilities.