Online retailer Shop Direct will close three sites in Greater Manchester, putting nearly 2,000 jobs at risk.
The group, which owns Very.co.uk and Littlewoods.com, said it would close its distribution centres in Shaw, Little Hulton and Raven.
It plans to build a new warehouse in the East Midlands employing 500 people, but said redundancies were likely.
Derek Harding, Shop Direct interim chief executive, said it was a “tough day for the business”.
“However, these proposals are necessary for our future and to enable us to continue to grow and meet rising customer expectations.”
Headquartered in Liverpool, Shop Direct is one of the UK’s biggest online retailers and traces its roots to a variety of mail order companies in northern England.
The firm, which also owns fashion portal Very Exclusive, is owned by the billionaire Barclay brothers, David and Frederick, who also own the Daily Telegraph newspaper titles.
Shop Direct said it would close the distribution centres from mid-2020 onwards and start operating in the East Midlands in 2021.
The site will be fully automated, which Shop Direct said would allow it to respond more quickly to changing consumer demand.
The move puts the jobs of 1,177 Shop Direct employees and 815 agency workers in doubt.
All of the affected Shop Direct employees are consulting with the firm about the changes, with the Usdaw union supporting staff.
Despite a recent slowdown on the High Street driven by weaker consumer confidence, online retail sales have proven resilient.
According to Shop Direct, its sales climbed 5.6% last year to £1.93bn.
Explaining its decision, the firm said the new site would allow it to process more orders and reduce the time it takes to get products to customers.