Cement manufacturing is to end at a plant in South Cambridgeshire and 87 workers are facing redundancy.
Cemex plans to stop cement making at Barrington and is meeting employee representatives to discuss details
A company spokesman said: "In total there are 87 employees on the site who are at risk of being made redundant."
The plant produces 250,000tpa of cement and production is to be transferred to "more efficient" plants in Warwickshire and North Lincolnshire.
"Cement manufacturing at Barrington involves feeding wet raw materials, mainly limestone and clay, into a kiln.
"Compared to Cemex’s two other plants, this traditional process requires significantly more energy to manufacture the product," the spokesman said.
The recent downturn in the economy and the slowdown in the construction industry are also factors influencing the closure of the plant.
President of Cemex UK, Gonzalo Galindo, said: "Barrington cement plant has been producing cement for nearly 80 years.
"The current economic climate has driven us to implement efficiencies and the closure of Barrington’s kiln could help to secure the future of our cement manufacturing business in the UK."