As many as 900 jobs are at risk with the announcement of the planned closure of two food factories in Leicester and Lincolnshire.
Bakkavor wants to close its Bakkavor Salads operation in Sutton Bridge, near Kings Lynn, and its Bakkavor Desserts factory in Leicester Forest East. There are 450 people working at each site.
The business, which reported UK revenues of £1.56 billion in 2020, produces meals, salads, pizza and bread, and desserts for the UK’s major store chains.
It said it was planning the closures as a result of the challenging "macro-economic backdrop" and a staff consultation was due to get underway.
A spokesman said: "As a business that invests in the development of its people, rewards long service and invests in the local communities in which we operate, it is with great sadness that this difficult but necessary business decision may impact a number of our colleagues.
"Across the two sites, we employ over 900 colleagues. We will shortly be commencing a 45-day consultation period with affected colleagues and their representatives at both sites.
"If the proposals go ahead, we will do everything we can to support our colleagues and try to minimise job losses.
“We are committed to offering our weekly paid colleagues comparable roles at a different Bakkavor site, and for those where this is not possible, we will be working on several initiatives to help colleagues secure alternative employment opportunities in their local area."
Bakkavor chief executive Mike Edwards said: "As with businesses all over the UK, we are having to take decisive action to adapt to the challenging macro-economic backdrop.
“The decision to close any site is never taken lightly, and we do not underestimate the impact of this announcement on our colleagues and the local communities within which we operate.
"We remain committed to both protecting our business and doing everything we can to support our people through this difficult time."
The Unite union has said it will be supporting members at both sites and trying to ensure redundancies are kept to a minimum with alternative employment offered at other sites in the group where possible.
