Bank of Japan policymakers were expected to discuss the effectiveness of recent tweaks to monetary stimulus at a two-day meeting that began Tuesday, with fresh policy changes unlikely amid stubbornly low inflation.

At its July meeting, the central bank's decision-making Policy Board said it would allow long-term interest rates to drift higher than it had previously allowed, a move Gov. Haruhiko Kuroda said made stimulus more sustainable by preventing the BOJ's bond purchases from soaking up liquidity and distorting the market.

In an apparent attempt to prevent the move from being viewed by financial markets as a tightening of its ultraeasy policy, the board also added forward guidance — a pledge to keep rates low "for an extended period of time" to ensure the economy can weather challenges including a consumption tax hike scheduled for next year.