Debenhams will consider closing up to 10 UK stores over the next five years as part of a strategic revamp of its business.
Its chief executive, Sergio Bucher, said Debenhams will become a destination for "social shopping" with a greater emphasis on mobile while maintaining good stores in strong locations.
The retailer will focus on expanding its beauty and fashion divisions and improve its leisure offering, while some brands and non-core international markets will be abandoned.
The approach is part of a new strategy intended to spur growth at the department store chain in an "uncertain" retail environment.
The department store chain reported revenues of £1.35bn ($1.73bn) in the six months to 4 March – a 2% improvement on the same period a year earlier.
Pre-tax profits slid 6% to £87.8m, in line with market expectations.
Online sales increased 15% year-on-year during the interim period, with mobile orders up 64%.
"Our customers are changing the way they shop and we are changing too," Bucher said in a statement. "Shopping with Debenhams should be effortless, reliable and fun whichever channel our customers use.
"If we deliver differentiated and distinctive brands, services and experiences both online and in stores, our customers will visit us more frequently and, having simplified our operations to make us more efficient, we will be able to serve them better and make better use of our resources."