Uncertainty over Scotland's currency arrangements could prompt capital flight from the country, leaving its financial system in a "parlous state," Douglas Flint, chairman of HSBC Holdings Plc, wrote in a column on Thursday in the Telegraph newspaper in Britain.
Flint said that sterling currency union was the anchor from which Scotland derives its economic success and financial stability.
Flint, chairman of Europe's biggest bank, said the decision by three major political parties to rule out a currency union with an independent Scotland was "wholly consistent with the actions that have been taken in the aftermath of the financial crisis" and "with the knowledge gained from recent events in the eurozone."
The question of whether Scotland could keep the pound if it voted on Sept. 18 to leave the United Kingdom has hampered independence campaigners. The British government has said no and Bank of England Governor Mark Carney has warned of difficulties in monetary union.
(Reporting by Karen Rebelo in Bangalore; Editing by Lisa Shumaker)