Tokyo, Oct 1 (IANS): The sentiments at Japan's big manufacturers worsened in September from three months earlier although going ahead firms are looking to boost investments, the Bank of Japan's (BOJ) Tankan survey showed on Thursday.

The diffusion index for large manufacturers, including automakers and the country's electronic producing behemoths, dropped 3 points to a reading of 12, marking the first decline in three quarters, with the latest reading coming in below median analysts' expectations, the survey showed, Xinhua reported.

But along with service-sector sentiment improving during the period, large manufacturers maintained robust capital expenditure plans as healthy profits have been booked recently, according to the survey.

It showed that they plan to boost spending by an average of 10.9 percent this fiscal year through next March, up from a revised 9.4 percent increase in June.

"Capital expenditure plans remain relatively firm and we have yet to hear of firms say they plan to significantly reduce or scrap spending plans in Japan," a Bank of Japan official was quoted as telling a press briefing following the survey's release.

The index for non-manufacturers, which comprises firms in both construction and retail-related businesses, rose 2 points to plus 25, beating median analysts' expectations, with the rise being attributed to robust office demand, falling energy costs and surging numbers of high-spending tourists from East Asia, according to the bank's officials.