One answer is for governments to co-operate more: to recognise each other's rules, as the European Union's members already do in the sale of financial services.

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And, as it happens, the best and most sophisticated arguments for downgrading the ratings of all eurozone governments, under the current constitutional arrangements for the currency union, were made in a recent speech by the chairman of the Financial Services Authority, Adair Turner (see my post, The eurozone's borrowing costs may stay lethally high).

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The credit union, which is a co-operative owned and controlled by members, offers financial services to anyone living or working in Surrey or the London borough of Kingston.

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Financial institutions: BBVA Bank, BMO, BNLPOSitivity, BNL Italy, BNP Paribas Fortis Belgium, Banco Sabadell, Banco Santander, Banca Sella, Citi, Commonwealth Bank, Deutsche Bank Italy, EMS, EnterCard, EURO 6000, European Merchant Services, Fifth Third Bank, Handelsbanken, International Card Services Netherlands, Intesa Sanpaolo, Lake Trust Credit Union, ME Bank, NAB, SEB Kort, SIA, Swedbank, TMG Financial Services, UniCredit and Westpac.

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Mr Van Rompuy thinks the banking union ought to cover the whole of the EU to avoid fragmenting Europe's single market in financial services.

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