Local business reports claim that Wal-Mart is to buy new shares in the loss-making department store and grocery business, also Japan's fourth-largest retailer, to raise its stake to more than 50 per cent from 42.4 per cent. Seiyu's shares rose up to 13 per cent on the speculation.
Wal-Mart and Seiyu both said no decision has yet been made, but Wal-Mart reiterated its plan to continue to work with Seiyu to improve the Japanese firm's performance.
Wal-Mart first took a 6 per cent stake in Seiyu in 2002 and has gradually raised its holding. The retailer has long had an option to boost its stake in Seiyu to 50.1 per cent by the end of this year.
French supermarket chain Carrefour announced it was pulling out of Japan in March after just four years.