TOKYO, Aug 30 (Reuters) - Japanese government bond yields fell on Monday, in line with U.S. Treasury yields after Federal Reserve Chairman Jerome Powell gave no new hints when the central bank is likely to start scaling back its bond purchases. The 10-year JGB yield fell 0.5 basis point to 0.015%. Benchmark 10-year JGB futures rose 0.09 point to 152.21, with a trading volume of 12,156 lots. On Friday, the 10-year Treasury note yield dropped more than 5 basis points to a session low of 1.3% as Powell’s remarks led investors to assume that a taper is unlikely until later in the year. “The contents of Powell’s comments were largely as expected, so that’s not what’s pushing down yields,” said Ataru Okumura, a strategist at SMBC Nikko Securities. “What’s pushing down yields is the unwinding of short positions preparing for a possible September start to tapering.” The 20-year JGB yield fell 0.5 basis point to 0.400%, while the five-year yield declined by the same margin to minus 0.120%. Two- and 30-year securities did not trade, with yields at minus 0.135% and 0.640%, respectively. (Reporting by Tokyo markets team; Editing by Subhranshu Sahu) Our Standards: The Thomson Reuters Trust Principles.