Britain’s second largest supermarket group,Sainsbury’s is cutting 400 jobs, with 4,000 other employees facing a major change to their working hours as part of a shakeup of how the retailer runs it supermarkets.

Sainsbury’s is the second largest chain of supermarkets in the United Kingdom,with a 16.9% share of the supermarket sector in the United Kingdom

Sainsbury’s is to scrap the role of price controller within its supermarkets, which will lead to hundreds of jobs being cut. Price controllers ensure that the price labels on supermarket shelves are accurate but this task will now be undertaken by other workers.

Sainsbury’s is also cutting night shifts in 140 stores, requiring 4,000 employees to move to either early morning or late evening shifts.

All of Britain’s big four supermarkets Tesco (TSCO.L), Sainsbury’s, Asda (WMT.N) and Morrisons (MRW.L) are seeking efficiency savings to finance price cuts so they can better compete with discounters Aldi and Lidl, who have won market share in recent years.

Unite, the country’s largest union, said it would be seeking guarantees over no compulsory redundancies at the supermarket giant Sainsbury’s,after the retailer announced plans which put over 4,000 workers at risk of redundancy.

Unite national officer for food and drink Julia Long said: ‘This is very bad news for those dedicated workers affected by the planned job losses and Unite will be giving our members maximum support at this difficult time.

‘We appreciate that Sainsbury’s has a good record of redeployment of staff in these situations and we will be exploring every avenue to ensure continuing employment for our members.

Unite represents more than 12,000 members working for Sainsbury’s and will now enter a 45 day consultation period over the plans which affects stores across the UK.

A Sainsbury’s spokesperson said: “We regularly review our business to ensure we are operating as efficiently and effectively as possible and our resources are in the right place, so that we can provide our customers with the best possible service.

“Following a recent review, we are making some changes to administrative roles and night shift patterns in a number of stores, subject to consultation.

“We appreciate this will be a difficult time for those colleagues affected by the changes and will support them in any way we can.”