Non-euro finance ministers discuss approach to crisis

The first such meeting was held by Swedish finance minister Anders Borg in Luxembourg last month, but there is "no rotation" or "precise calendar" of upcoming similar gatherings, one source said. "It is not a club of 10," another diplomat said, "just an invitation to an informal dinner."

Although nominally belonging to the same group, the countries have diverging views on the common currency and the EU. The UK and Denmark have opted out of the obligation on EU members to join the euro, while Latvia, for instance, is still very keen on joining the currency. Romania wants a "United States of Europe" while the Czech Republic is more eurosceptic. Sweden, Poland and the rest of the central and eastern-European countries are also legally bound to eventually join the euro.

However, they are tied together by one common concern - that a two-speed Europe is being constructed leaving the easterners out and the British financial markets vulnerable to "constant attacks" from EU legislation penned without Britain's consent, as Prime Minister David Cameron put it two weeks ago.

The non-euro country grouping is one of a series of ad hoc formations that are springing up as the EU struggles to get to grips with its crisis.

Last month, the so-called Frankfurt Group emerged. This ad-hoc formation consists of the leaders of Germany, France, eurozone finance ministers, the chiefs of the European Central Bank, the European Commission, the European Council and the International Monetary Fund and first came together in Frankfurt - the seat of the ECB - during the farewell party of Jean-Claude Trichet, the former head of the bank.

It was during this first gathering that France and Germany's deep division about the role of the ECB became apparent. It was also this same formation that in the margins of last week's G20 meeting in Cannes showered Greek Prime Minister George Papandreou with criticism over his referendum plans.