European Commissioners are set to make interest rate rigging a criminal offence after the LIBOR scandal, according to reports.
Regulators have turned their attention to at least four of Europe's largest banks in a continued investigation of manipulation of the LIBOR benchmark interest rate.
Senior FSA executive Andrew Bailey has accused Barclays of operating with a "culture of gaming" which came from top of the bank.
The US Federal Reserve raised concerns about LIBOR as early as 2007 and shared proposals for reform with the UK regulator, according to reports.
Brussels is proposing new rules to prevent the manipulation of LIBOR as part of a crackdown in the wake of the rate-fixing scandal.
The Royal Bank of Scotland (RBS) is to challenge a court order requiring it to co-operate with an international criminal investigation into rate-fixing.
Barclays shares are in demand, despite the fall-out from the LIBOR scandal and Bob Diamond's resignation, with investors buying five shares for every one sold.