Tokyo-based Maruetsu Inc. and Ibaraki-based Kasumi Co., affiliates of Aeon Co., will join Chiba Prefecture-based subsidiary MaxValu Kanto Co. in a single holding company by next March, Aeon said Monday, in a statement issued jointly with the two affiliates and Marubeni Corp.

The four companies said they will seek to increase the number of outlets to 1,000, with sales totaling ¥1 trillion in the region by 2020 and thereby become Japan's largest supermarket alliance. The three chains had a total of about 450 outlets as of last February.

Aeon and Marubeni will set up an entity to take a majority stake in the holding company, which will list on the Tokyo Stock Exchange after Maruetsu and Kasumi delist from it next February.

Aeon currently has a stake of around 30 percent in both Maruetsu and Kasumi. Marubeni owns a similar stake in Maruetsu.