Shares of Mizuho Financial Group fell as much as 7.7% on Monday after the Japanese lender clarified that it has yet to decide on an investment in Rakuten Bank.

The clarification came after Yomiuri Shimbun reported Sunday that Mizuho planned to make additional investments in the major online bank, citing informed sources.

Mizuho currently holds a 14.99% stake in Rakuten Card Co., the credit card and financial services unit of Japanese e-commerce and internet services giant Rakuten Group.

Yomiuri Shimbun reported that Mizuho plans to withdraw its stake in Rakuten Card and invest in Rakuten Bank instead.

Mizuho said it was exploring various options, “including the possibility of investing in Rakuten Bank,” but that no decision had been made.

The newspaper also reported that Mizuho Securities Co.’s 49% stake in Rakuten Securities would remain unchanged.

Analysts are keeping an eye out for any upcoming announcements Mizuho may make regarding Rakuten Bank.

“Currently, the [Fintech] segment of Rakuten Group is undergoing reorganization, scheduled to be completed in Oct 2026 whereby the bank, card and securities will be reorganized in the same group,” Jefferies analysts said in a note.

The worst-case scenario for Rakuten Bank would be to overpay for its securities and card segments, but direct intervention by Mizuho could avert that, Jefferies analysts added.

The news comes after Mizuho posted a 660% increase in its fourth-quarter profit from a year ago. Net profit for the quarter ending in March surged to 228.7 billion yen ($1.44 billion) compared with 30.1 billion yen a year ago, helped by factors including strong growth in its fee business and a higher central bank policy rate.

Mizuho’s shares last traded 7.2% lower, while Rakuten Bank rose more than 8%.