Britain's financial regulator said today it has done "basic contingency planning" in case Scotland votes this month to become an independent country.
But should Scotland leave the UK, lawmakers in Edinburgh would have to decide how their financial market should be regulated, Financial Conduct Authority Chairman John Griffith-Jones said.
"We have done some basic contingency planning," Griffith-Jones told parliament's Treasury Select Committee.
The rival Scottish campaigns are running neck-and-neck nine days before the referendum, with a surge in support for those who wish to break away, a TNS poll showed today.
The poll follows one in a Sunday newspaper that put the pro-independence camp ahead for the first time this year.
The FCA's plans include "making sure that phone lines are properly manned if people ring up, making sure we have a position around what advice would be appropriate to be given around day one," Griffith-Jones said.
Working out the detail was likely to "turn out to be complicated," he added.
Meanwhile, the Bank of England Governor said a currency union between an independent Scotland and the remainder of the UK would be incompatible with sovereignty.
Mark Carney today recalled a speech he made in January in which he said a successful currency union would require cross-border agreements on tax and spending as well as on banking rules.
He also noted the opposition of Britain's three main political parties to a currency union with an independent Scotland, as proposed by the Scottish nationalists.
"So it's in that context, if you put it together, a currency union is incompatible with sovereignty," he added.