TOKYO, Feb 19 (Reuters) - The Japanese government bond yield curve steepened slightly on Wednesday as the market braced for new supply of superlong maturities.
The Ministry of Finance offered 1.2 trillion yen ($11.72 billion) of 20-year JGB notes on Wednesday, with the auction results due at 1300 GMT.
Market participants expect the new 20-year paper to attract ample demand from investors.
The lead 10-year JGB futures inched up 0.02 point to 144.95, lifted by a slip in Tokyo shares.
The benchmark 10-year note yield stood unchanged at 0.600 percent.
The 20-year yield rose 0.5 basis point to 1.460 percent. The yield spread between 10-year and 20-year notes widened by 0.5 basis point to 86 basis points.
The market's medium-term focus is on whether the Bank of Japan will ease monetary policy again in the foreseeable future.
The central bank stood pat on Tuesday, keeping monetary policy unchanged as widely expected, but in a bid to help buoy economic growth it extended its special loan programmes - a move seen by some market participants as a possible precursor to future easing.