The Treasury Department auctioned $34 billion in five-year notes at a high yield of 1.218 percent on Tuesday.
The bid-to-cover ratio, an indicator of demand, was 2.29, lower than a recent average of 2.45.
Indirect bidders, which include major central banks, were awarded 57.2 percent, lower than a recent average of 59 percent. Direct bidders, which includes domestic money managers, bought 3.7 percent, lower than a recent average of 8 percent.
Peter Boockvar, managing director and chief market analyst at The Lindsey Group, characterized the auction as "weak." He said that the bid-to-cover ratio was at its "lowest level in almost 7 years."
The yield on the moved higher following the auction to 1.1920 percent. It was last higher at 1.969 percent.
U.S. sovereign bond bond prices were lower Tuesday as safe-haven trades continued to unwind alongside fresh polls that showed positive gains for the remain campaign in Britain's EU referendum.
The yield on the 10-year Treasury note, which moves inversely to its price, moved higher to 1.7051 percent, while the yield on the 30-year Treasury bond was up at 2.5071 percent. yields was also higher at 0.7655 percent.
Investors seem to have breathed a small sigh of relief as the most recent polls ahead of the U.K.'s June 23 referendum on EU membership showed the remain camp moving ahead. The latest poll released by YouGov/The Times shows 42 percent likely to vote remain, 44 percent to leave, and 9 percent undecided. Meanwhile the ORB poll for The Telegraph newspaper showed the remain camp opening up a 7 point net lead at 53 percent versus 46 percent likely to vote to leave.
Federal Reserve watchers were digesting testimony from Chair Janet Yellen, who was speaking in front of the U.S. Senate Committee on Banking, Housing and Urban affairs.
Yellen said in prepared remarks that global risks and a U.S. hiring slowdown warrant a cautious approach to raising interest rates.
Yellen will later appear at the Treasury Department's Financial Stability Oversight Council alongside Treasury Secretary Jack Lew at 4:30 p.m. ET to discuss the council's 2016 annual report.
Federal Reserve Governor Jerome Powell will also speak today, appearing in New York at a roundtable for the Interim Report of Alternative Reference Rates Committee at 2:30 p.m. ET.
Treasury auctions scheduled for Tuesday include one for $34 billion of 5-year notes.
No major data are expected.
—Reuters contributed to this report.
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