US 10-year note and 30-year bond yields, which move inversely to prices, climbed to two-week peaks, while those on two-year notes advanced to a more than one-week peak after hitting a nine-year high last week.

Cheng Chen, interest rates strategist at TD Securities in New York, attributed the rise in yields to Yellen's hawkish comments.

"Yellen was kind of optimistic about the economy," said Chen. "She's basically saying that strong growth would drive inflation higher and I think that's one of the drivers for the market moves today."

In what may be one of her last public appearances before leaving the Fed chair early next year, Yellen said on Wednesday a strengthening US economy will warrant continued interest rate increases. She made the remarks before US congressional leaders.

Data showing that US gross domestic product expanded at a 3.3 percent annual rate in the third quarter further boosted yields. That was the quickest pace of US growth in three years, as increases in business investment in inventories and equipment offset a moderation in consumer spending.

"After a good third-quarter, the survey and early monthly evidence point to another decent gain in GDP in the fourth quarter of between 2.5 percent and 3.0 percent annualized," said Paul Ashworth, chief US economist, Capital Economics in Toronto.

In mid-morning trading, the 10-year Treasury yield was up at 2.386 percent, from 2.337 percent late on Tuesday. It hit a two-week high of 2.395 percent.

US two-year yields, which climbed to a nine-year peak last week, were at 1.774 percent from 1.758 percent on Tuesday. Two-year yields, the most sensitive maturity to rate hike expectations, touched a one-week peak of 1.778 percent.

US 30-year bond yields were up at 2.827 percent from Tuesday's 2.765 percent. Earlier, 30-year yields hit a two-week high of 2.837 percent.

Tom di Galoma, managing director at Seaport Global Holdings in New York also attributed part of the selling in Treasuries that bolstered yields to the sell-off in UK bonds.

British 10-year government bond yields rose by the most in a day since June, lifted by reports Britain was close to a deal with the European Union on how much it needs to pay to exit the bloc.

The yield on 10-year gilts rose by as much as 10 basis points to 1.357 percent, their highest level in almost a month.