The bank last hiked its main rate to 2.50% in May 2018 and has since tightened money market liquidity via market operations which it said gave it more flexibility.

"By tightening liquidity controls we have managed ... to keep money market rates at levels above 3.2 percent, that would be the equivalent of three (quarter-point) rate decisions, so monetary policy is significantly tighter," Isarescu said.

He added that the bank could not deviate too far from the monetary policy stance of the European Central Bank and other central banks in the region, which have mostly shied away from hiking their main rates.

"We have opted for market operations," Isarescu told reporters.

"We will probably need to diversify our intervention tools on the money market to react faster."

Inflation came in above expectations in April at 4.1pc, above the bank's 1.5-3.5pc target range, partially reflecting a slew of new taxes.

Meanwhile, economic growth sharply exceeded expectations at 5pc in the first quarter, likely driven by domestic consumption, which combined with rising budget and current account deficits will put pressure on the central bank to tighten policy.

Isareacu said the bank expects inflation to stay above its target for the next three quarters.

The bank will release new inflation forecasts for this year and next on Friday.

Romania has four elections this year and next.

The Romanian leu was flat at 1420 GMT.

All analysts polled by Reuters had forecast Wednesday's decision and most see rates remaining at the same level at the end of the year.

"While we continue to see rates on hold this year and tightening via twists in policy implementation, we attached a material probability to rate hikes, especially if the Romanian leu comes under renewed depreciation pressures," ING Romania said in a research note.