HSBC is to consider moving its headquarters out of the UK, chairman Douglas Flint revealed today.
Mr Flint said the banking giant was responding to "regulatory and structural reforms" in the industry in the wake of the financial crisis.
These include, in the UK, the need to separate its investment banking arm from the retail division serving ordinary customers and businesses.
Mr Flint said: "As part of the broader strategic review taking place, the board has therefore now asked management to commence work to look at where the best place is for HSBC to be headquartered in this new environment.
"The question is a complex one and it is too soon to say how long this will take or what the conclusion will be, but the work is under way."
HSBC, which originated in Hong Kong, has been based in the UK since 1992 when it took over the UK's Midland bank and shifted its headquarters to London. The global group employs 266,000 people, including 48,000 in the UK.
Mr Flint said it was "essential that we position HSBC in the best way to support the markets and customer bases critical to our future success".
HSBC said last month that it was to relocate the head office of its UK retail bank to Birmingham by 2019, in a move that will see 1,000 jobs transferred from London, as part of this "ringfencing" separating different arms of the business.
The bank has recently come under intense pressure over the activities of its Swiss private banking arm amid claims that it helped thousands of account holders hide billions of their assets from tax authorities in their home countries.
The scandal resulted in Mr Flint and Stuart Gulliver being ferociously grilled by MPs and apologising for "unacceptable" activities at the Swiss unit.
It is facing criminal investigation in other countries including France where the bank was earlier this month ordered to post one billion euro (£720 million) bail.
Mr Flint acknowledged the scandal in a statement to the bank's Annual General Meeting in London, saying: "The recent past has been very difficult for HSBC."
He apologised "for the inadequacies in controls that allowed unacceptable behaviours to occur undetected and accept responsibility for restoring HSBC's reputation and standing to where they should be".
Mr Flint added: "HSBC has paid a heavy price. Our reputation has been damaged."
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