Bob Diamond, the Barclays CEO once described as the unacceptable face of capitalism, is facing pressure to resign after a rate-fixing scandal hit his bank.
On Wednesday, an FSA investigation found that Barclays manipulated the rates at which banks lend to each other.
Emails from within the bank show traders brazenly asked one another to change the Libor rate, the interest rate which banks charge when lending to other banks which can affect student loans, mortgages and credit cards, with replies saying: "Done, for you big boy".
Diamond, who was in charge of Barclays Capital at the time the breaches occurred between 2005 and 2009, apologised and said he and three other key executives would waive their bonuses for this year.
Liberal Democrat peer and the party's former Treasury spokesperson Lord Oakeshott put the spotlight on Diamond, saying if he had a scintilla of shame, he would resign."
"If Barclays' board had an inch of backbone between them they would sack him."
Former Barclays chief executive Sir Martin Taylor has said the bank should explain who knew what when about the practices.
He told BBC Radio 4's Today programme on Thursday that "somebody at senior level somewhere will have known."
"These organisations are very large, as I know myself, and the chief executive doesn't always know everything that's happening in the organisation, though he's responsible for setting the tone of the organisation."
Barclays were fined £290m after the scandal was discovered - and it is believed more banks could be caught up in the dirty dealing.
Chair of the Treasury select committee Andrew Tyrie has said he will haul in Diamond to explain the scandal.
Labour leader Ed Miliband has called for a criminal investigation into the matter, saying in a speech on Thursday morning: "This cannot be about a slap on the wrist. The public who are paying the price for bankers' irresponsibility will expect nothing less."
George Osborne is expected to make a statement on the matter at lunchtime.
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