Major department store operators Mitsukoshi Ltd. and Isetan Co. are close to agreeing on April 1 as the date for their merger under a joint holding company, sources familiar with the matter said Aug. 20.

With combined sales of about ¥1.58 trillion, the merged entity would become Japan's top department store group, surpassing J. Front Retailing Co., which will be created in September through the merger of Matsuzakaya Holdings Co. and Daimaru Inc.