TOKYO Seven & i Holdings has decided to sell department store unit Sogo & Seibu on Sept. 1, triggering a plan by union workers to strike at the flagship Seibu store, the Nikkei business daily reported on Wednesday.

If the strike goes ahead as planned on Thursday, it would be the first at a major Japanese department store in about 60 years.

Japan-based Seven & i, operator of the world's largest convenience store chain, agreed last year to sell Sogo & Seibu to Fortress Investment Group. But the deal has been delayed amid opposition from workers, who had notified management of the strike earlier this week.

Fortress had initially planned to spend around 250 billion yen ($1.71 billion) on the acquisition but is likely to have lowered that price by about 30 billion yen, the Nikkei reported.

($1 = 146.1900 yen)

(Reporting by Kantaro Komiya and Chang-Ran Kim)