The leu opened at 4.218/4.22 to the euro, stronger than 4.223/4.225 at closing the day before.
Later, the leu continued to strengthen and, at around 10:30 local time, it was trading at 4.205/4.207 against the euro.
The central bank set Monday a reference rate of 4.2192 lei to the euro, RON0.032 weaker on the day.
On the money market, overnight rates were at 4.25%-4.75% a year.