TOKYO, Dec 26 (IFR) - Japanese government bond prices were mostly lower on Friday as some investors booked profits ahead of the weekend, after the benchmark yield set a fresh record low earlier in the session.

The Bank of Japan bought 400 billion yen ($3.33 billion) of JGBs in the 5-year to 10-year zone under its massive asset purchase programme. The offer-to-cover ratio rose from 2.56 times at its last purchase offer on Dec. 17 to 3.11 times, the highest level since 3.35 times on Nov. 21.

Investors widely expect the central bank to buy another 400 billion yen of JGBs in the 5-year to 10-year zone on Monday, in addition to 900 billion yen in the 1-year to 5-year zone.

Data released on Friday showed Japanese annual core consumer inflation slowed for a fourth straight month in November due largely to sliding oil prices, highlighting the challenges the central bank faces in achieving its 2 percent inflation target.

The yield on the current 10-year JGBs hit a fresh record low of 0.300 percent earlier, but it was last up 1.5 basis points at 0.325 percent.

Lead March JGB futures soared as high as 147.95 in the morning session, a new record high, before closing down 0.14 points at 147.69.

The yield on the current 5-year JGBs added 1 basis point to 0.045 percent,

In the superlong zone, the 20-year yield added 2 basis points to 1.070 percent, after dropping as low as 1.025 percent earlier in the session, its lowest level since April 2013.

The 30-year JGB bucked the downtrend, its yield edging down 2 basis points to 1.225 percent.

($1 = 120.2000 yen) (Reporting by Masatsugu Hisatsune; Editing by Biju Dwarakanath)