A growing number of Bank of Japan policymakers are warming to the idea of ending negative interest rates this month on expectations of hefty pay hikes in this year's annual wage negotiations, four sources familiar with its thinking said.

But an imminent policy shift is hardly a done deal as there is no consensus within the nine-member board on whether to pull the trigger at its upcoming March 18-19 meeting, or hold off at least until the subsequent meeting on April 25-26, they say.

Many BOJ policymakers are closely watching the outcome of big firms' annual wage negotiations with unions on March 13, and the first survey results to be released by labor umbrella group Rengo on March 15, to determine how soon to phase out their massive stimulus.