Britain's banks will be embroiled in a fresh scandal over complex financial products which have landed small businesses with spiralling bills.
The Financial Services Authority (FSA) is expected to reveal that it has found evidence of mis-selling as part of a review into the way lenders pushed so-called interest rate swap arrangements (Irsas).
Irsas are complicated derivatives products that may have been sold as protection - or to act as a hedge - against a rise in interest rates without the customer fully grasping the downside risks. Some companies have claimed the rising fees required to service the product after interest rates fell in 2008 have forced them out of business.
The City watchdog is expected to confirm that banks are writing to customers who have taken an Irsa and an independent assessor will look at the most complicated cases and determine whether compensation should be paid.
The claims echo the payment protection insurance (PPI) scandal that emerged last year, costing banks billions of pounds, and come in the week Barclays was fined £290 million for manipulating interest rates.
Businesses have complained that Irsas, which were designed to insure borrowers against steep rises in interest rates, left them swamped by huge penalties after interest rates were slashed to record lows in the wake of the financial crisis.
Customers will be dealt with in two categories according to whether they were sold relatively simple products or those of a more complex nature, Sky News said. the latter group are expected to be told that their case will be reviewed by an independent assessor and that they will be compensated if there is evidence of mis-selling.
A debate in the House of Commons last week saw MPs from across the country offer examples of mis-selling for the interest rate swap products.
Aberconwy MP Guto Bebb claimed thousands of businesses lost large amounts of money after being mis-sold the complex products by their banks, and many were told that without signing up they risked being refused credit.
A survey by Bully Banks, which has been set up by alleged victims of swap mis-selling, found nearly three-quarters of its members claim to have been forced to buy a swap by their lending bank as a condition of their loan.