• Will a too strong krona spoil the Swedish party?

The Swedish krona is the world’s best performing major currency this year. Now the Scandinavian country's Finance Minister Anders Borg warns that further gains in the krona would be a cause for concern.

“Were we to see a considerable strengthening from” current levels, “I would think that would be worrying,” Anders Borg told Bloomberg News, however adding that "the exchange rate is currently at a reasonable level".

The krona has rallied as Sweden delivers the biggest economic rebound in the European Union. In the past 12 months the krona has risen 9 percent against the euro and 14 percent against the dollar.

However, some say that the Swedish currency still is undervalued.

“Sweden is moving away from high, persistent current- account surpluses and part of that, of course, is due to the exchange rate, which we judge is still undervalued,” Carl Hammer, chief foreign-exchange strategist at SEB in Stockholm, told Bloomberg.

Carl Hammer expects the krona to strengthen to 8.4 against the euro by 2012 and to trade “a bit below that” in 2013, he told the news bureau.

Sweden's GDP increased 7.3 percent in the fourth quarter compared to the fourth quarter of 2009, beating analyst expectations. Sweden's central bank February hiked its key interest rate for the fifth time since July, bringing it to 1.5 percent. The economy will grow 4.2 percent this year as employment reaches the highest level in two decades, the National Institute for Economic Research said.