US Treasuries gained on Tuesday as the Federal Reserve made new purchases of longer-dated debt, and as hope faded that there would be an agreement for a stronger euro zone rescue fund. Month-end buying also lifted prices as investors moved to lock in gains seen after the Fed said last week it would likely hold interest rates near zero until late 2014.
Bonds had softened earlier, a move traders attributed to talk that the United States, European Union and International Monetary Fund were stitching together a 1.5 trillion euro ($1.98 trillion) rescue for euro zone countries.
Optimism soon faded, though, and hopes Greece would strike an agreement Tuesday with its creditors to restructure its debt also receded as the day went on without a deal, traders said.
The speculation followed a speech by IMF chief Christine Lagarde in which she urged leaders to boost support for the euro zone as it struggles to tame a debt crisis.
"I think there's some skepticism over this 1.5 trillion bailout," said Scott Graham, head of Treasuries trading at BMO Capital Markets in Chicago. At the same time "there's some deal flow today and a 30-year buyback. The combination of those two is somewhat bullish."
The Fed bought $2.52 billion in bonds due between 2036 and 2041 from $5.01 billion submitted by dealers on Tuesday as part of its Operation Twist program, which is designed to lower long-term borrowing rates.
That helped push benchmark 10-year notes up 12/32 in price to yield 1.80 percent. Thirty-year bonds gained 1-7/32 in price to yield 2.94 percent.
Despite the Fed's buying, 30-year yields were on track to end the month about five basis points (0.05 percentage points) above where they began. Benchmark yields shed seven basis points.
Five-year yields outpaced both, dropping 12 basis points this month after the Fed said interest rates would remain near zero for the better part of the next three years.
"I had investors tell me before that they would never buy a five-year Treasury, but they were soon forced into it," said Michael Pond, Treasury and inflation-linked strategist at Barclays. "So it has been partly a month-end trade today."
Krishna Menami, director of fixed income at Oppenheimer Funds, said low rates and anxiety about Europe would likely conspire to keep yields in a low, narrow range this year.