By Mari Murayama and Kanako Chiba
Tokyo, Nov. 8 (Bloomberg) -- The yen had its first decline against the dollar in six days as some Japanese bank stocks tumbled, fanning concern investor confidence in the nation's banking system is waning.
The yen weakened as low as 121.38 per dollar before trading at 121.25 from 121.03 yesterday in New York.
``Concern that Japan's banking sector may deteriorate will hurt the yen,'' said Shohgo Nagaya, foreign exchange manager at Nomura Trust and Banking Co.
Asahi Bank Ltd. fell as much as 33 percent on investor concern the lender, Japan's fifth largest, isn't releasing enough information on its plan to merge with rival Daiwa Bank Ltd.
The banking sub-index of the Nikkei 225 stock index yesterday dropped to an 18-year low.