Scotland and EU: Alistair Darling and Blair Jenkins
14 December 2012 Last updated at 14:29 GMT
Former Chancellor Alistair Darling claimed the nationalist position on Scotland remaining in the EU and keeping a currency union with the UK was a "deceit".
And Mr Darling, who speaks for the Better Together campaign, said the independence campaign was "flying by the seat of their pants".
But Yes Scotland chief executive Blair Jenkins said it was "inconceivable" for Scotland not to remain within the EU, and and no-one was seriously suggesting otherwise.
He said East Germany joined the union "overnight" when it merged into enlarged Germany, and he called on the rival campaign to withdraw claims that Scotland would be forced to join the EU currency.