Kuroda, however, is sticking to his two percent inflation target, if not the timeline. The BOJ recently postponed its target date to the fiscal year 2016, from 2015.
"Our target is 2 percent consumer price inflation (CPI) and not just touching 2 percent, but [that] inflation should stay at 2 percent for the coming years," he said. "And as you know almost all major central banks aim at 2 percent…I think the target is reasonable."
Weaker currencies for weaker economies
The yen has depreciated nearly thirty percent since the BOJ launched its quantitative easing (QE) program last year and the U.S. dollar was fetching 123.74 yen in early Asia trading time after the Japanese currency tapped eight year-lows.
The governor insisted that many factors, not just monetary policy, cause currency movements.
"Although the dollar has recently appreciated against the euro and yen, our monetary policy has not changed since April 2014, [and] we have been implementing so-called QE faithfully and in the meantime, the exchange rate fluctuated," he said.
The yen has in fact been depreciating since Prime Minister Shinzo Abe, who appointed Kuroda, was returned to power in the December 2012 elections. In the months running up to Abe's re-election, the yen was still trading at around 80 against the U.S dollar, at 17-year highs.
But while Kuroda said the BOJ's policies aren't the only driver of the yen, the currency has swooned every time the central bank has eased.
In the month following the first QE announcement, the yen depreciated by nearly eight percent, and by over 12 percent in the month after the program was expanded at the end of October 2014.
QE until growth cometh
Still, Kuroda insisted that weaker economies will need to keep the QE tap turned on to simulate growth and inflation.
"The [U.S.] Federal Reserve is likely to normalize its monetary policies because the U.S. economy is the strongest among the three economies. The Eurozone and Japan's economies are not as strong as U.S.'s, so I think Europe and Japan will continue QE for some time," he said.
One sign of how the BOJ's QE program is doing will come on Friday, when April's consumer price data will be released. The median forecast is for a 0.20 percent on-year rise in core nationwide consumer prices, according to a Reuters poll of 21 economists.
Many economists are predicting the central bank will have to expand its QE program again as early as in October, to demonstrate its renewed commitment to its 2 percent inflation target.