Bank of Japan (BOJ) policymakers remained unwavering in their resolve to keep massive monetary stimulus, even as some saw signs of change in the country's low-inflation environment, minutes of their March policy meeting showed on Monday.

Several in the nine-member board said some big firms were raising wages and companies were more eagerly passing on rising raw material costs to households, which could put upward pressure on consumer inflation, the minutes showed.

Japan's consumer prices rose the fastest among major advanced economies during the global inflationary cycle in the 1970s, which meant there was always a chance inflation could spiral higher once price hikes broaden, one member noted.