As the FT notes:
As part of the new measures to clamp down on tax avoidance, UK residents will also be obliged to tell the British tax authorities when they open certain foreign bank accounts.
The new reporting requirement will apply to UK residents opening accounts in “certain” offshore jurisdictions, with heavy penalties of up to 200 per cent of unpaid tax for those who fail to comply.
Accountants believe the new rule is likely to be applied in tax havens, such as the Channel Islands, a popular financial centre for UK residents.
The Revenue have had enough of cheating in the Channel Islands and Isle of Man. And rightly so. So things are going to get tough for their banks and for their trust companies - because UK residents are going to have to report if they use them.
There's no excuse now for a bank in these places saying it did not know that a customer was tax evading in the UK: I think they will have to ask in future and make sure declaration is made or not provide services.
But I bet they won't do that, all the same. And if they don't it will prove what I've always suspected - that they deliberately want tax evaded funds. If they don't they've certainly been very good at getting them none the less.