Treasury 30-year bond momentum "is turning bullish," and the debt may be poised to pare the worst losses since 2009, according to Royal Bank of Scotland Group Plc, citing technical analysis.

Weekly slow stochastics, a measure used to predict a security's movement based on how close its price is to its highest or lowest levels, are signaling stronger sentiment for the long bond after indicating weakness since May, according to William O'Donnell and John Briggs, interest-rate strategists in Stamford, Connecticut, at the bank's RBS Securities unit.

"The price momentum of the selloff has been losing thrust in recent weeks as the market has become oversold," said O'Donnell, head U.S. government-bond strategist at RBS, one of 21 primary dealers that trade with the Federal Reserve. "We may be looking at the end of bearishness and a phase of lower rates."