TOKYO, Nov 20 (Reuters) Japan's Nikkei average tumbled on Tuesday to a 16-month low, hit by a faltering dollar and Wall Street slide, with a Citigroup downgrade renewing fears about credit and the health of the U.S. economy.
Attention was on Japanese lenders Sumitomo Trust&Banking Co and Aozora Bank Ltd after the Nikkei business daily said they plan to form a comprehensive business alliance with eyes towards a possible merger.
As of 0002 GMT the benchmark Nikkei was at 14,859.31, down by 183.25 points or 1.2 percent, its lowest since July 27, 2006.
The broader TOPIX index was down 1.2 percent at 1,438.74, its lowest since Oct. 2005.
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