The crown dropped 0.6 percent on the day to as low as 25.85 to the euro, the lowest since Dec. 28 last year.

The currency has been closely watched as it has traded weaker than central bank forecasts, raising speculation that policymakers may hike interest rates earlier than their own outlook pointing to a move around the end of the year.

The bank has lifted its main rate to 0.75 percent in three steps since last August.