TOKYO, June 4 (IFR) - Japanese government bond prices sagged on Wednesday, taking cues from a sharp fall in U.S. Treasuries, though short-covering ahead of a shift in benchmark futures helped to limit losses.

The Bank of Japan reduced buying in the 3-5 year zone to 200 billion yen ($1.95 billion) from 250 billion yen while increasing its buying in the 1-3 year sector to 300 billion yen from 250 billion yen in its bond buying.

The changed had limited impact on the overall market as such moves had been anticipated.

The 10-year cash JGB yield rose 1.0 basis point to 0.615 percent while the 20-year JGB yield rose 1.0 basis point to 1.450 percent.

The 10-year JGB futures price dipped 0.03 point to 145.34 , supported by buy-back ahead of the expiry of the benchmark June contract next week.

The 10-year U.S. Treasury yield jumped to 2.59 percent from 2.53 percent the previous day.

($1 = 102.4300 Japanese Yen) (Reporting by Masatsugu Hisatsune; Editing by Jacqueline Wong)