10% fall for sterling?
U.K. lender Lloyds, meanwhile, is considering moving its registered office to London rather than Edinburgh, according to Reuters who quoted an anonymous source from the banking industry. For these banks, a "yes" vote could cause serious short-term pain, according to Rob Wood, the chief U.K. economist at Berenberg Bank. Wood agrees that some financial firms may move south and uncertainty about currency arrangements and the status of Scotland in the European Union would surge.
"Long term, Scotland would be forced into austerity," he said in a morning research note on Wednesday, adding that it would also raise the risk of the U.K. leaving the European Union.
Nonetheless, over the longer term, sterling remains a "sell" according to some analysts, even if the Scots do vote "no". Kit Juckes, the global head of foreign exchange strategy at Societe Generale believes that last year's build-up of sterling "long" positions haven't been fully unwound. The currency had seen a strong appreciation in recent years with stellar data form the U.K. helping it higher with traders anticipating that the Bank of England could be looking to hike its main interest rate next year.
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"A fall below 1.60 is likely in due course," Juckes said in a note on Wednesday morning. "If they were to vote 'yes', you could add another 3-5 percent or so to the potential downside. And if the U.K. decided to leave the EU, you could probably add another 10 percent at least."
But not all agree on this long-term scenario. Eimear Daly, the head of market analysis at Monex Europe, believes sterling is likely to regain its strength and trade back towards the £1.68 level. Daly has been bullish on the pound for several months and correctly predicted the break above the $1.70 level earlier this year.
In the short term, she told CNBC via email that if Scotland were to vote "yes", then sterling-dollar would see an immediate sharp sell-off, breaking below $1.63 and heading towards $1.60.
"The protracted negotiations that would follow a 'yes' vote would be horrific for investor and consumer uncertainty. This would affect third-quarter growth as businesses delayed deals and investments and consumers cut back on big ticket items until the political and regulatory environment becomes more certain," she said.