The central bank bought treasuries from four lenders and will sell them back April 23.
Last week, the central bank injected RON5.93 billion into the market in a one-week repo.
The central bank has been injecting cash into the market every week since October last year, and governor Mugur Isarescu said the bank has been increasing liquidity on a regular basis because some of the local lenders have difficulties borrowing from their peers.
Market participants believe some of the local banks use the money to fund the Finance Ministry at lower yields.
On the money market Monday, weekly rates were at 2.5%-3% a year, slightly up from 2.1%-2.6% a year Friday. (EUR1=RON4.3733)