TOKYO, June 6 (Reuters) - Japanese government bond prices inched down on Tuesday with the market weighed down by an overnight slip in U.S. Treasuries, although firm demand for new 30-year debt helped contain the losses.
The benchmark 10-year JGB yield was half a basis point higher at 0.050 percent. The 20-year yield was unchanged at 0.560 percent.
The bid-to-cover ratio, a gauge of demand, at Tuesday's 800 billion yen ($7.28 billion) 30-year JGB auction rose to 3.63 from 3.35 at the previous sale.
The new JGBs were seen to have attracted ample investor demand as the 30-years had become relatively cheap compared to other super longs like the 20-years.
Treasury debt prices fell on Monday, as investors booked profits after gains the previous session on a U.S. employment report that underwhelmed expectations and suggested a more cautious Federal Reserve policy beyond June. ($1 = 109.8400 yen) (Reporting by the Tokyo markets team)