The Bank of Japan on Wednesday decided to keep monetary policy on hold, but one board member tried unsuccessfully to loosen the central bank's commitment to achieving its 2 percent inflation target within two years.
In a unanimous vote, the BOJ maintained its pledge to increase base money, or cash and deposits at the central bank, at an annual pace of 60 trillion to 70 trillion yen ($585-$682 billion).
BOJ board member Takahide Kiuchi proposed that the central bank make its 2 percent inflation target a medium- to long-term goal, and commit to intensive easing in the next two years. This would differ from the BOJ's current commitment to hit its inflation target within two years.
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Kiuchi's proposal was rejected in an 8-1 vote.
On April 4, the BOJ eased policy by pledging to double the supply of money in two years by boosting purchases of government bonds and risky assets.
In doing so, it switched its policy target from the overnight call rate target to base money, a broad measurement of the amount of money the central bank pumps into the economy.
The BOJ also upgraded its assessment of the economy on Wednesday to say it has started picking up.
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The BOJ's statement did not mention recent increases in government bond yields.
BOJ Governor Haruhiko Kuroda will hold a news conference from 0630 GMT with his comments expected to come out any time after 0715 GMT.