The final cost to the country's banks for payment protection insurance (PPI) mis-selling is likely to be about £25bn, according to The Times.
It means they will have to pay double the £13bn already set aside to cover the scandal, according to calculations using the Financial Services Authority's (FSA's) monthly PPI pay out figures and historic selling data, the paper said.
If banks are forced to refund every PPI fee they ever generated the bill could be as high as £40bn.
The Bank of England is taking the worst case scenario suggestion seriously, the paper said, and uncertainty over PPI accounts for some of the £35bn black hole in bank balance sheets identified by the Bank.
