TOKYO, Feb 18 (Reuters) - Japanese government bond prices were steady to firmer on Monday after the Bank of Japan refrained from trimming its buying, with the benchmark 10-year JGB futures edging near their 2-1/2-year high touched last month.
The Bank of Japan (BOJ) maintained the size of its JGB purchase in its operation on Monday; and bought four maturities zone - one to three, three to five, 10 to 25, and 25 to 40 years.
Some market players had expected the BOJ to reduce its bond buying given that the 10-year yield has stayed below the BOJ's policy target of zero percent in recent weeks.
The benchmark 10-year JGB futures rose 0.06 point to 152.89, edging near the 2-1/2-year high of 152.99 hit last month.
The benchmark 10-year cash JGB yield fell 0.5 basis point to minus 0.03 percent. The five-year JGB yield dropped 0.5 basis point to -0.175 percent.
The longer end of the market was capped by caution ahead of Tuesday's auction of 20-year JGBs.
The 30-year JGB yield and the 40-year JGB yield were at 0.590 percent and 0.665 percent respectively. (Reporting by Tokyo markets team, Editing by Sherry Jacob-Phillips)