Recent global market turmoil and uncertainty about the U.S. economy haven't dented confidence at major manufacturers, a closely watched Bank of Japan survey showed Oct. 1.

The central bank's quarterly tankan survey of corporate sentiment showed the key confidence index for large manufacturers stood at 23 in September, unchanged from June. Analysts had predicted the index, which measures the percentage of companies reporting that business conditions are better minus those reporting that conditions are worse, would fall to 21 amid worries about the global fallout from problems in the U.S. credit market.

The survey, which polls more than 10,000 companies, suggests that Japan's big exporters are more upbeat than many had expected.

"As for business investment, I was concerned about its future course after the GDP data came out, but now it has been reconfirmed that it remains healthy," Economy Minister Hiroko Ota said.