The average yield rose to 6.13% from 6.08% achieved in the previous auction of twelve-month government debt paper held on November 5, the central bank, which sells government securities on behalf of the finance ministry, said on its website.
Bids were placed for 1.35 billion lei worth of T-bills in Monday's auction.
The finance ministry has sold 48.7 billion lei and 421.5 million euro ($538.8 million) in government securities on the domestic market so far this year.
Romania has also sold $2.25 billion in dollar-denominated bonds on the U.S. market and 2.25 billion euro in euro-denominated bonds on international markets since the beginning of 2012.
(1 euro = 4.5292 Romanian lei)