SCOTTISH independence cannot be compared to the “back-of-a-fag-packet” plans for Brexit, an SNP minister has said.

Europe Minister Neil Gray’s comments come after Nicola Sturgeon unveiled her plans for the economy in an independent Scotland, with the third in a series of papers designed to refresh the prospectus for an independent Scotland.

The First Minister said Scotland would continue to use Sterling after a Yes vote, only moving to a new Scottish pound when a number of requirements are met, including when the country is fiscally sustainable.

Sturgeon repeatedly refused to say how long that period would last, but intimated in an answer to one journalist that she hoped it would be less than five years.

READ MORE: What to make of the First Minister's gradualist plan for Scotland's economy

In the economic prospectus, the Scottish Government said the transition period's length and management would be a case for the Scottish Parliament. 

The First Minister also said there would be border checks on two major trunk roads and rail freight terminals between Scotland and England in the event of the country gaining EU membership.

She also said renewable energy would be the “bedrock” of the economy of an independent Scotland as North Sea revenues decline.

Speaking on BBC Radio Scotland on Tuesday, Gray rejected comparisons to the Brexit campaign.

“We have produced already three prospectus papers, we’ve got more to come in the series, where we’re setting out the case to the people of Scotland, giving them the information so they can make an informed choice,” Gray said on Good Morning Scotland.

“It’s not possible to compare the well-informed choice that people in Scotland are going to make over independence with the back-of-a-fag-packet case that was presented to people before the Brexit referendum.”

He added: “We’ve got a plan not just to put to the people of Scotland in terms of a choice to make, but also one that would inform our state building after a Yes vote in an independence referendum.”

No unified prospectus was put forward before the 2016 referendum on leaving the EU.

When asked if he believes Monday’s paper will shift opinion in favour of independence, Gray simply said: “Yes.”