U.S. Treasurys prices rose on Thursday after the euro zone's chief central banker said policymakers will decide early next year if the slowing region needs more economic stimulus.
Prices of 30-year Treasurys, which had been stung early this week by investors positioning for a flurry of high-quality corporate debt offerings, increased 15/32. Long bonds were last yielding 2.966 percent, according to Reuters data.
European Central Bank President Mario Draghi told reporters in Frankfurt that the ECB's Governing Council was unanimous in backing such potential steps as a government bond-buying program with new money.
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The ECB also cut its 2015 economic growth and inflation forecasts and kept borrowing costs at record lows.
New forecasts by ECB staff sharply downgraded the euro zone's growth outlook for next year to 1.0 percent from the 1.6 percent predicted in September.