The nation's two leading department store chains, Takashimaya Co. and Mitsukoshi Ltd., announced Thursday they will study the integration of their distribution and information networks.

The move is aimed at reducing operating costs at a time when department stores are suffering a prolonged sales slump amid sluggish consumer demand.

The two firms will integrate and streamline some 100 distribution centers in the Tokyo metropolitan area and put home delivery services, such as those for summer and winter gifts, under joint operation. They will also seek to integrate managerial work such as placing orders and maintaining buildings.

If realized, it would save several billions of yen annually in distribution costs.

Apart from distribution, the two firms also plan to carry out a joint study of electronic commerce and other new business fields.

The two firms said they will call on other department stores to join their plan.

The move announced by the two companies is likely to accelerate the ongoing industrywide move toward the integration of so-called back-office operations -- those that are not directly linked to their main line of business and respective business strategies.

Such discussions have been conducted under an initiative of the Japan Department Stores Association, to which the top department store chains belong.

Takashimaya, the largest chain, is already cooperating with 14 companies, including Keio Department Store Co. and Maruei Department Store Co, in product delivery. Mitsukoshi, the second-largest, has a similar alliance with Daimaru Inc.