In what figured to be the final push for Prime Minister Shinzo Abe to go ahead with raising the consumption tax to 8 percent in April, the Bank of Japan's "tankan" report Tuesday showed a sharp increase in business sentiment among manufacturers.

Benefiting from a weaker yen induced by Abe's ultra-loose fiscal policies dubbed "Abenomics," the sentiment index for big manufacturers — companies capitalized at ¥1 billion or more — climbed to 12 in the three months through September compared with a score of 4 in June.

Abe had said that Tuesday's tankan numbers, which are determined by subtracting the percentage of companies with bad business sentiment from companies with a positive outlook, would be one of the final factors considered in judging whether to go forward with the sales tax hike.