Nicola Sturgeon wants a second referendum on independence
Although the SNP had campaigned for independence based on the hope Scotland would be able to keep the pound and retain the Bank of England as its central bank, civil servants were asked to come up with a blueprint for a £50m-a-year 'Scottish Monetary Institution' (SMI).
The secret papers also suggested the cost of the SMI would be "considerably larger" if the UK government, as it had promised to do, refused to let Scotland keep the currency.
The plans were revealed through secret government documents released under a Freedom of Information request by The Scotsman.
But after Scotland voted to remain in the UK, SNP sources have indicated to the Scotsman that the SMI plans could be dusted off as the the party begins building the case for a second independence vote.
The documents evision an independent Scottish bank but with a large number of central banking functions still carried out by the Bank of England.
It estimated a workforce of about 450 people, at a cost of £24m a year, icluding a £16m wage bill.
In total, the total running cost of the SMI in its forst year was estimated to be £49.7m.
Nicola sturgeon wants a second independence referendum
However, the dcoument concedes: "If no agreement is reached with the UK government and the Bank of England does not undertake a large number of central banking functions on behalf of the SMI, then the remit of the SMI would need to be significantly expanded and the number of staff required would be considerably larger."
Opposition parties in Scotland said the documents reveal the SNP's muddied thinking over the economics of an independent Scotland.
Both Labour and the Conservatives said the report was an embaressing indictment of SNP policy, which was why it had never come to light until now.
A Scottish Government spokesman said the documents demonstrated the "thoroughness" with which Holyrood had prepared for the possible outcome of the 2014 referendum.
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