Almunia says 'undesirable' to act on Sweden's euro refusal

"This is why, although it is theoretically possible in the future to initiate infringement procedures against states which are not preparing themselves, at the moment we are not considering this necessary, not even desirable," he said.

Sweden, which entered the EU in 1995, is legally obliged to enter the eurozone, an obligation enshrined in its EU accession treaty as in the case of ten member states that joined the union in 2004.

Non-euro members UK and Denmark, on the other hand, have negotiated an opt-out from the single currency.

The European Commission and the European Central Bank regularly assess the economic performance of countries obliged to join the single currency, with Sweden fulfilling the key criteria on inflation, budgetary deficit and interest rates, according to a report last year. The next assessment is due in November.

But following the no vote in Sweden's euro referendum in 2003 the issue has not come back onto Stockholm's agenda, despite the fact that the referendum had a consultative and non-binding force only.

According to Mr Posselt who raised the issue in a special Q&A session with the monetary commissioner, Sweden's attitude sets a bad example for other countries gearing up to join the euro.

"They have ratified the accession treaty so how come they can organise a referendum and refer to it for not fulfilling the rules in this treaty?" he told EUobserver.

"This is a union of laws and rules. And member states can't just pick up one rule that they don't like and just ignore it. If they said - we need five or ten years to prepare, it is ok with me - but just to be quiet about the issue and do nothing is unacceptable."

Swedish political party unhappy

Meanwhile, Mr Almunia's statements sparked negative reactions in Sweden.

Swedish MEP Halene Goudin from the Junilistan party which campaigned under a banner to stop Sweden from joining the eurozone demanded that the commission clarifies that it supports the result of the Swedish referendum and that it rejects demands that Sweden adopts the euro.

"A vast majority of the Swedish people has in a referendum said no to joining the EMU. Member Posselt wants to run over the referendum result. This is not compatible with a democratic view," Ms Goudin told the plenary in Strasbourg.

"The Swedish economy has not been affected negatively by the fact that we stand outside the common monetary union. On the contrary, Sweden has good growth and low inflation," the Swedish MEP continued.

Newcomers may follow the suit?

But Mr Posselt argues that Stockholm's attitude could lead the new member states to take a similar line.

So far, Poland and Hungary have said they might organise a euro referendum, with the Hungarian socialist officials saying before the spring parliamentary elections that they would secure euro entry even if the vote result was a no.

Other "new" member states argue the issue has already been decided as part of the EU membership package and should not be questioned.