JPMorgan Chase & Co, the biggest bank in the US, lost $5.8 billion in 2012 from disastrous credit bets.

Around $4.4bn of those came in the second quarter of the year although the bank still generated almost $5bn of profit for the period.

JPMorgan said it had cleaned up its Chief Investment Office, which made the bad trades, although it admitted that a further $700 million to $1.7bn could be lost.

Bruno Iksil, the trader nicknamed "The London Whale" due to the positions he took in the credit derivatives markets, is understood to have left the bank.

Chief executive Jamie Dimon said: "We have put most of this problem behind us and we can now focus our full energy on what we do best."