Scottish First Minister Alex Salmond, speaking to BBC News 24, accused the Chancellor of "political sabre-rattling".
This is a Tory Chancellor trying to scare people in Scotland, trying to stop them voting for independence.
But the day after a resounding Yes vote in the referendum, when people sit down and start to negotiate in the best interest of the people of Scotland and the rest of the United Kingdom, he will sing an entirely different tune."
It's in everyone's interests to have a currency area after independence - it's in the interests of Scotland, it's also overwhelmingly in the interest of the rest of the United Kingdom.
He said that was for the "very simple reason that huge Scottish resources such as oil and gas would continue to protect the sterling balance of payments"
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