Scottish first minister Alex Salmond shot back today after UK Treasury chief George Osborne last week ruled out a currency deal.
Osborne said Scotland would walk away from the pound should it vote for independence on September 18.
But Salmond says businesses in the rest of the UK will potentially pay "many hundreds of millions" in transaction costs.
Salmond dubbed these charges a "George Tax" and predicted it would be impossible "to sell to English business," that they might be charged "for the privilege of exporting goods to Scotland."