Barclays (LSE: BARC.L - news) is locked in negotiations with the City regulator about signing up to an industry-wide admission that British banks mis-sold complex derivatives products to thousands of small business customers.
I have learnt that Barclays, which is reeling from the £290m in fines imposed on Wednesday by UK and US financial watchdogs, has yet to sign up to an agreement that will be announced on Friday morning by the Financial Services Authority (FSA) about the mis-selling of interest rate swaps.
Along with the taxpayer-backed Royal Bank of Scotland (LSE: RBS.L - news) (RBS), lawyers acting for Barclays are taking their discussions with the City regulator to the wire. I understand that the FSA statement will name the banks which have signed up to its agreement - and, by omission, those which have not.
My understanding is that the FSA will say that approximately 28,000 customers were sold the swaps, which were designed to insure those who purchased them against steep interest rate rises.
As my colleague Jason Farrell has been reporting, some customers were forced out of business because of the mountainous costs that the ultra-low interest rate environment triggered.
I have obtained further details of Friday's FSA announcement, which will point to "serious failings" in the way the swaps were sold.
It will say that there was poor disclosure of the costs associated with exiting the swaps; that there were inadequate steps taken by the banks to ensure customers understood the risks associated with the products; and that some customers were sold the swaps by bank employees who were not authorised to sell them.
I revealed earlier that the banks which sign the agreement will inform customers who were sold the more exotic swaps products that their cases will be reviewed by an independent assessor.
Those who were found to have been the victims of mis-selling will be eligible for compensation, which is likely to be calculated as the difference between the losses they incurred and the cost of taking a fixed-rate loan from the same bank.
Barclays and RBS are wavering over signing the FSA agreement because as the biggest suppliers of the swaps, they are likely to be liable for the heftiest compensation bills.
City figures say the two banks will nonetheless be taking a significant risk if they do not sign up because they will again place themselves in the political firing line by being seen to try to obstruct the resolution of another major bank mis-selling scandal.
A Barclays insider told me he expected the bank to sign the agreement but that it might not happen in time for Friday's announcement.
The FSA and the banks declined to comment tonight.