TOKYO, May 19 (IFR) - Japanese government bond prices dipped slightly on Monday as the market geared up for new supply of superlong maturities, while a rise in U.S. Treasury yields on Friday also weighed on JGBs.
The Ministry of Finance will auction 1.2 trillion yen ($11.8 billion) of 20-year JGBs on Tuesday.
The June 10-year JGB futures contract fell 0.05 point to 145.23.
The benchmark 10-year JGB yield rose 0.5 basis point to 0.585 percent.
A break below 0.570 percent would take the 10-year yield to a one-year low. The yield, already under sustained downward pressure from the Bank of Japan's aggressive monetary easing, has fallen 3.5 basis points so far this month, in line with a recent fall in government bond yields globally. ($1 = 101.4600 Japanese yen) (Reporting by Masatsugu Hisatsune; Editing by Eric Meijer)