Bank of Japan policymakers engaged in heated debate when deciding to adopt negative interest rates last month, with dissenters of the move arguing that economic conditions weren't bad enough to warrant such a drastic step, a summary of the board meeting showed Monday.

“Japan’s economic activity and prices have maintained stable conditions, and the recent instability in financial markets has not been serious. At this moment, the bank does not need to implement additional monetary easing,” one of the nine board members was quoted as saying at the meeting.

At the January meeting, the BOJ unexpectedly cut a benchmark interest rate below zero, stunning investors with another bold move to stimulate the economy as volatile markets threaten its efforts to overcome deflation.