The leu closed at 4.289/4.2915 per euro, from 4.2815/4.2825 per euro Tuesday.
Elsewhere in the region, the Hungary’s forint was losing 0.8% versus the euro, while the Polish zloty was down 0.4%.
The leu opened down at 4.288/4.290 per euro, and further lost ground, hitting the day’s low of 4.297 per euro.
“If the concerns over the troubles in the euro area widen, the exchange rate could break through the psychological threshold of 4.3 units this week,” ING Bank said in a report.
The central bank set the leu’s reference at 4.2886 to the euro, the weakest rate this year. However, leu advanced 0.3% against the US dollar, trading at 3.1346 units.
On the money market, overnight rates rose to 4.5%-5% a year, from 4.1%-4.6% a year Tuesday.