Masayuki Koguchi, executive chief fund manager at Mitsubishi UFJ Asset Management, suggests the Bank of Japan may need a larger or unscheduled rate hike. He stated a standard 25 basis point increase might prove insufficient to counter the yen's ongoing decline.

Koguchi proposed a jumbo hike of 50 or 75 basis points at a single meeting if inflation begins to accelerate. He also noted that an out-of-cycle rate increase remains a possibility depending on economic fundamentals and the external environment.

The executive's comments highlight a growing view within Japan's financial sector that the central bank requires more decisive action.