Alex Salmond said the campaign against Scottish independence had suffered a “demolition” blow following a UK minister's claim that the pound would be shared in the event of a Yes vote.
Treasury ministers were forced to intervene and insist there would be no currency union after an unnamed coalition minister was reported yesterday as saying a deal could be brokered to allow Scotland to maintain a currency union with the remainder of the UK.
Alex Salmond said the comments had shown that the No campaign's stance on sterling "is a campaign tactic, a negotiating position, something to scare the natives up in Scotland."
The comments also prompted Alistair Darling, who heads the Better Together group, and shadow chancellor Ed Balls to stress a shared pound "wouldn't happen, no matter what anonymous quotes people read."
Mr Salmond told Sky News's Murnaghan programme: "You would not have had the panicky reaction of the last 48 hours...if the No campaign didn't realise that their scaremongering has been holed below the water line.
"It has been a very difficult 48 hours for the No campaign and it's going to get a lot worse because they are not basing their arguments on a positive vision of the future.
"They have based their arguments on whatever they can say or do in this campaign to try and intimidate the people of Scotland out of voting for independence and their bluff is being called.”
Earlier, a UK cabinet minister admitted that victory for the Yes campaign in the Scottish independence referendum is “not impossible”.
Alistair Carmichael, the Scottish Secretary, said Britain risked losing Scotland because of complacency among unionists who leave it “too late” to make their voices heard.
The Liberal Democrat minister’s comments come at a potentially critical point in the independence debate, after it emerged that another minister, who has remained anonymous, claimed Scotland could join keep the pound as part of a currency union with the rest of the UK.
Sending out a message to those who are pro-union but yet to do anything about it, Mr Carmichael told The Observer: “The danger is that by the time they realise it could happen, it could be too late.
“Everybody needs to know that this is a serious contest, and one which it is not impossible that the nationalists could win.”
Mr Carmichael said that the pro-independence campaign had the capacity to “buy momentum” in the build-up to September’s vote, in a way that the Government does not.
“We're never going to match them for the spend, but in terms of the hunger I think we have to match them for just how badly we want this,” he said.
Chancellor George Osborne and his Lib Dem deputy Danny Alexander were forced to intervene to insist that Scotland would not be able to form a currency union in the event of independence after an unnamed minister's comments appeared to undermine one of the key elements of the No campaign's strategy.
The two senior Treasury ministers said: “The Scottish Government are proposing to divorce the rest of the UK but want to keep the joint bank account and credit card.
“The UK would not put its taxpayers at risk of bailing out a foreign country and its banks. Parliament wouldn't pass it, and the people wouldn't accept it.
“Any suggestion to the contrary is wrong.”
All three main parties at Westminster have officially ruled out sharing sterling with an independent Scotland and made it a key plank of the No campaign, but an unnamed minister was quoted in The Guardian as saying “of course” there would be an agreement on the pound, indicating that a deal could be done with Scotland in exchange for the UK's nuclear submarine fleet remaining at Faslane.
Alistair Darling, who leads the cross-party Better Together campaign, said today: “A currency union would not be good for Scotland or the rest of the UK. That's why it wouldn't happen, no matter what anonymous quotes people read.
“Using the pound isn't just about the money in our pockets. It's essential to keeping costs down for families and support the public services we rely on every day - from schools and hospitals, to pensions and benefits. Alex Salmond's obsession with breaking up the UK puts that at risk.”
Speaking on Sky’s Murnaghan programme, Mr Salmond said the UK’s refusal to share the pound was “bluff” dreamt up to “scare the natives up in Scotland”.
He said the positive message of the Yes campaign would win out over the negatives of the No campaign, and added: “We are going to urge people to vote for an optimistic vision of the future.”