Alpine banking secrecy might be viewed by Washington, Berlin and London as incompatible with their crusade to crack down on tax dodging but, for the Swiss, it is a guiding principle of their nationhood.

James Nason, a spokesman for the Swiss Banking Association trade body, said: "A state that demands an automatic right of forced entry into bank accounts has a toxic relationship with its citizens and is basically telling them it doesn't trust them an inch but is corroded with suspicion about their financial activities."