Last weekend Tuomioja wrote in his blog that "the whole compact is at best unnecessary and at worst harmful, and Finland has reason to oppose the whole treaty and at least remain outside it." He also called the proposed new rules a "senseless straitjacket," and made similar comments in an interview with the Financial Times.

Katainen said that such comments cause difficulties in explaining Finland’s true position, adding to the overall ministerial workload. He said that Finnish ministers should not stray too far from the government line, particularly when talking to foreign media.

In his opinion, Tuomioja’s comments were made in a personal capacity, and his own views were utterly opposed to those Tuomioja expressed.

“Finland has been in favour of stricter budget discipline, has demanded it from others and has wanted to commit to tighter financial rules for the common good and for our own benefit,” said Katainen.

Finland is reportedly close to a deal with the eurozone on a new voting system for the EU bailout fund. The compromise would remove an obstacle to launching the fund next summer.

Eurozone leaders have agreed that the European Stability Mechanism can make urgent decisions on loans to troubled countries with a majority of 85 percent of votes, rather than unanimously.

Finland is the only country that opposes the change. It would require the support of two-thirds of the Finnish parliament -- a majority the current government lacks.