Mizuho Financial Group plans to increase its investment in Rakuten’s online securities arm, which isn’t proceeding with an initial public offering for now.

Japan’s third-largest banking group will raise its shareholding in Rakuten Securities to 49%, slightly more than a year after it bought about 20% of the firm and formed a business alliance. The deal is valued at ¥87 billion ($576 million) and scheduled to close on Dec. 15 subject to regulatory approval, according to a joint statement on Thursday by Mizuho and Rakuten.

Rakuten also said it will withdraw its listing application for its securities unit and will reapply for an IPO at an appropriate timing. The holding company for Rakuten Securities, part of billionaire Hiroshi Mikitani’s e-commerce giant, had earlier applied for an initial share sale of the unit.

A move by the brokerage to cut its commission on domestic stock trading to zero was seen as putting pressure on the its IPO price ahead of a listing, Bloomberg reported last month.

The freeze on these IPO plans comes as Rakuten Group faces a growing need to raise funds with losses at its mobile phone carrier business adding up. Even though it listed its online banking unit earlier this year, there may be more to be done. The most pressing task for Rakuten is to raise funds for more than $5 billion of bonds due in the next two years.

Meanwhile, the additional investment is seen as positive for Mizuho, according to Michael Makdad, an analyst at Morningstar in Tokyo. As Rakuten Securities has the second largest number of individual brokerage accounts in Japan, the deal "could help Mizuho Securities narrow the gap in its domestic retail securities business to round out the success Mizuho has had in global wholesale securities business,” he said.