Interest rates on short-term Treasury bills rose in Monday's auction to the highest levels in several weeks.

The Treasury Department auctioned $28 billion in three-month bills at a discount rate of 0.160 percent, up from 0.115 percent last week. Another $28 billion in six-month bills was auctioned at a discount rate of 0.215 percent, up from 0.170 percent last week.

The three-month rate was the highest since three-month bills averaged 0.165 percent on May 24. The six-month rate was the highest since those bills averaged 0.220 percent on June 1.

The discount rates reflect that the bills sell for less than face value. For a $10,000 bill, the three-month price was $9,995.95 while a six-month bill sold for $9,989.13. That would equal an annualized rate of 0.162 percent for the three-month bills and 0.218 percent for the six-month bills.

Federal Reserve policymakers met last week and repeated their pledge to hold interest rates at record lows for an "extended period" to fuel economic growth.