The problem with Japan's Zengin interbank financial settlement network that began Tuesday remained unresolved as of Wednesday morning, the operator said.
The system is unlikely to be restored Wednesday, according to Zengin-Net, also known as the Japanese Banks' Payment Clearing Network.
Zengin-Net said that it will work to reduce the impact of the problem by using alternative means, but there may be delays in financial transfers across 11 banks.
The affected banks are MUFG Bank, Resona Bank, Saitama Resona Bank, Kansai Mirai Bank, Yamaguchi Bank, Kitakyushu Bank, Mitsubishi UFJ Trust and Banking, Custody Bank of Japan, JPMorgan Chase Bank, Momiji Bank and Shoko Chukin Bank.
MUFG Bank has set restrictions on some services as a result, such as accepting orders for transfers to other banks only until noon.
Transfer orders the bank accepted the previous day are scheduled to be processed Wednesday. MUFG Bank will also handle money transfers to its accounts from other banks in stages.
The glitch has affected around 1.4 million money transfer orders starting from 8:30 a.m. on Tuesday, according to Zengin-Net.
The problem is believed to be traceable to update work on a relay computer program conducted between Saturday and Monday.
On Tuesday, Japan Post Bank saw its internet banking and some other services disrupted by a separate system glitch. The services returned to normal within the day, with the exception of the Yucho Bankbook app.
According to the bank, Yucho Bankbook services had not been restored as of 11 a.m. Wednesday.
"The Zengin system is at the core of the country's financial settlement system," Chief Cabinet Secretary Hirokazu Matsuno told a news conference, calling for careful responses to customer requests and efforts to restore the system as soon as possible.