Barclays' share price has plummeted more than 8% this morning amid calls for boss Bob Diamond to quit in the wake of the LIBOR scandal, and ahead of a speech from George Osborne on the debacle later today.
The bank was fined £290m by UK and US regulators yesterday for breaching LIBOR rules, after being found to have illegally influenced the rates which banks borrow from each other.
While shares held up yesterday, this morning they tanked, and are currently down 8.34% or 16p, to 179.70p.
Other banks said to be under investigation are also under pressure, with RBS down 5.5% or 12.8p, at 220.4p.
The FTSE 100 is down 1% at 5,464.
Politicians have now waded into the row, demanding answers from Diamond and his colleagues.
The Treasury is preparing to make an emergency statement on events at the bank at 12.15pm today.
Prior to the statement David Cameron said this morning: "I think the whole management team have got some serious questions to answer. Let them answer those questions first."
Meanwhile, Labour leader Ed Miliband has called for a criminal investigation to take place.
Others, including Liberal Democrat Treasury spokesman Lord Oakeshott, have called on Diamond to quit.
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