"This is very strong appreciation, we cannot ignore it," Tuma told Bloomberg. ``By definition this pace of appreciation is unsustainable. That is clear.''
The koruna has appreciated by 7.5% against the euro and 16% against the dollar over the last five months. One euro was worth Kcs28.74 on 2 July but just Kcs26.70 on Monday. A greenback bought Kcs21.14