The country's biggest banks have been accused by MPs of a massive mis-sale of complex interest rate swaps to thousands of businesses, the Telegraph reports.
Politicians from all major parties named Barclays, HSBC and Royal Bank of Scotland (RBS) among lenders who had forced small business to buy the products - which, the report said, had bankrupted some firms.
Tory MP Mike Freer, a former senior banker at Barclays, said he was "shocked and appalled" one of his constituents had been treated.
Another Conservative, Gary Streeter, said: "It is truly a scandalous story. I suspect it will become as big a scandal as the mis-selling of payment protection insurance."
It said the swap products were supposed to protect against rinsing interest rates but in some cases customers have been left with costs of hundreds or even millions of pounds they say they were not warned about.
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