Not that long ago, the banks and the Conservative Party were seen as natural allies. Any half-respectable Tory cabinet minister could count on a bank chairmanship to crown his dotage. Not any more, of course.

Weekend comments by Alan Duncan, the Shadow Business Secretary, represent a new frostiness in the party's relationship with banks, particularly credit card operators.

Vulnerable consumers were being seduced into debt that they couldn't possibly afford to repay, Mr Duncan said. “They'll [the banks] suck them in and then they'll spit them out.”

Nought per cent teaser offers were unacceptable and would be looked at by the Conservatives, he said, accusing banks of creating “human misery” through their aggressive marketing of debt.

Not since David Cameron took a swipe at WH Smith for positioning chocolate oranges enticingly close to the checkouts has his party so publicly smacked big business.

Post Northern Rock and with the credit crunch quite probably leading to a serious global slowdown, the banks are perhaps seen as fair game. They seem even less loved than usual.

Politicians and regulators are increasingly concerned by the pricing of bank products, pricing that bears no relationship to the underlying cost to the bank and sometimes seems designed primarily to dupe.

Mr Duncan's concern is that once the initial cheap lending rate vanishes, vulnerable people are locked in and obliged to pay a much heftier interest rate.

The Competition Commission, which is currently investigating payment protection insurance (PPI), is thought to be particularly concerned about the cross-subsidy element in PPI.

Loans and credit card debt is offered cheap, but the banks rake in abnormally large profits on the PPI sold alongside it.

Banks are in a difficult position. Their products are intangible and very hard to differentiate.

But that is not a good reason for introducing ever more confusing pricing structures or weaselly conditions.

patrick.hosking@thetimes.co.uk

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