The BOJ pledged to keep interest rates "very low" for the time being and took measures to make its massive stimulus programme more flexible, reflecting its forecast that it would take time for inflation to hit its 2 per cent target, Reuters reported.
Investors had been geared up for a change in the BOJ's massive stimulus programme to allow for greater swings in interest rates and a wider stock-buying initiative.
"The Bank of Japan look like they are being a bit more flexible but certainly not dramatically changing things, so the yen is weakening a little," said Phil Borkin.
"There's just a bit of relief that they aren't dramatically changing the policy stance," he said.
Locally he said the kiwi largely overlooked weak business confidence data as "domestic drivers aren't really in the box seat at the moment....it just reminds the market that the economy here isn't amazingly healthy and that will cap the upside for kiwi moves."
A net 45 per cent of 340 firms surveyed in the ANZ business outlook survey for July expect general business conditions to deteriorate in the coming 12 months, 5 points lower than June's result and the lowest that measure has been since May 2008.
Looking ahead, Borkin said investors will now be focused on the US Federal Reserve as well as the Bank of England and tomorrow's New Zealand jobs data may garner some interest.
Economists are tipping a steady second-quarter unemployment rate but some expect signs of wage inflation on a higher minimum wage and slowing migration.
The main event, however, will be jobs data in the US at the end of the week.
The trade-weighted index increased to 73.33 from 73.17 and the kiwi traded at 91.85 Australian cents from 91.90 cents yesterday. It was at 4.6570 Chinese yuan from 4.6434 yuan and at 51.99 British pence from 51.85 pence yesterday and was almost unchanged at 58.28 euro cents from 58.27 cents.
New Zealand's two-year swap rate fell one basis point to 2.12 per cent and 10-year swaps were unchanged at 3.02 per cent.
