Scottish Liberal Democrat leader Willie Rennie will tell an audience in Edinburgh this evening that Scotland's global reputation would be trashed if the nationalists follow through on their threat of defaulting on Scotland's share of the UK debt.
The remarks comes after Finance Secretary John Swinney confirmed that his party would default on an independent Scotland's share of UK debt if it did not get its way on a currency.
Speaking at an event with leading members of the Edinburgh Asian community, Mr Rennie will say:
"One of the first acts of a newly independent Scotland would be to tell the rest of the world we were defaulting on our debt. This would trash our global reputation before we'd have time to raise the saltire up the flagpole outside St. Andrews House.
"You don't have to be an economics professor to know that refusing to pay your mortgage comes with consequences.
"The price of the default will be high with the international markets refusing to trust an independent Scottish Government that it will repay future debts.
"That is why I want Scotland to stay part of the UK, where we can share risk and reward across broader shoulders. This position is in stark contrast with the nationalists reckless passion for their independence plans.
"Increasingly desperate nationalists are now resorting to idle threats that could cost Scotland dear. Their passion for their cause blinds them to the consequences of their position.
"Refusing to take on an independent Scotland's share of the debt would look like and smell like a default. Those are not my words but the words of Crawford Beveridge, Alex Salmond's currency advisor.
"We may not like it, but the powerful forces that are the international money markets would see John Swinney's refusal as a default. And with that comes consequences which the nationalists have not addressed.
"If on day one of an independent Scotland Alex Salmond refused to shoulder our share of debt, the international markets would eat us alive. It would be families, employees and businesses across Scotland who would pay the price with higher mortgage bills, credit card payments and personal loan charges.
"Only today, 130 businesses raised their concerns about the nationalists independence plans. 130 employers, who all play a significant role in driving our economy forward and creating jobs in fishing, mining, food, whisky and technology sectors. It would be foolish and reckless for the nationalists to brush off their concerns.
"It would foolish for the nationalists to make an assumption that their position in government outranks the experience of 130 employers operating in Scotland as part of the UK. It would be reckless for the nationalists to seek out comfort in their own voices whilst the employers of hundreds of thousands of people across Scotland demand answers to unanswered questions in currency, tax and pensions.
"Anything short of detailed answers from the nationalists on these crucial concerns about their plans can only spell bad news for employees and businesses."