Japan's Financial Services Agency is making final coordination to issue a business improvement order against Mizuho Financial Group and its banking unit following a series of system glitches.
Mizuho Bank experienced four system failures in less than two weeks starting in late February. The incidents included bank cards and passbooks getting stuck inside automatic teller machines, forcing customers to wait for hours at the site.
System trouble also halted over-the-counter transactions nationwide in August.
Earlier this month, a malfunction in the bank's core computer system knocked out about 100 ATMs and internet-banking services.
Officials want the bank to report in detail how it has checked its systems and made revisions to them. They plan to strengthen their supervision to prevent a recurrence of a similar problem.
The officials also plan to continue their inspection of the bank, which has been going on for about six months, to verify the cause of the trouble as well as the responsibility of executives for it.
This will be the third business improvement order against Mizuho by the Financial Services Agency. The agency penalized the bank in 2002 and 2011 for large-scale system failures.