Serious Fraud Office, the UK body that investigates and prosecutes serious and complex fraud, has launched a formal investigation into suspected fraud at Kaupthing, the Iceland-based integrated financial services provider, prior to its collapse at the height of the financial crisis.

SFO is particularly interested in efforts made to attract UK investors to the purportedly high yield deposit account, Kaupthing Edge. The investigation will seek to identify whether misrepresentations or false representations were communicated by the bank in the push to attract UK investors.

Another focus for the SFO investigation will be the decision making processes, which appear to have allowed substantial value to be extracted from the bank in the weeks and days prior to its collapse.

A spokesman at SFO said: "This is a complex investigation which crosses numerous jurisdictions. We have been working closely with the Icelandic Special Prosecutor’s Office to ensure that comprehensive and robust investigations are conducted both in Iceland and the United Kingdom and to ensure that there is no duplication of effort. We will continue to do so."