International credit rating agency Fitch said Monday it has placed Asahi Bank on "rating watch negative," following the bank's announcement last week that it is in talks with Daiwa Bank over a business integration.

Fitch currently assigns a BBB-plus long-term debt rating, F2 short-term rating, and D/E individual rating to Asahi Bank, but gives an E individual rating -- the lowest on its scale -- to Daiwa Bank.

The rating agency said, "With stock prices slumping worldwide and especially weak market conditions in Japan, Asahi's shares have come under speculative attack in recent days amidst a variety of rumors, which the bank describes as 'without foundation.' "