The First Minister said leaving the EU without a deal would “inevitably cause disruption” whatever the Government does to prepare.

Scottish Government ministers agreed to step up preparations at a Cabinet meeting yesterday, claiming Boris Johnson’s apparent refusal to negotiate with the EU has made a no-deal Brexit more likely.

After the meeting, Ms Sturgeon warned that, “even with the best possible preparations, leaving the EU without a deal will hurt Scotland’s businesses, disrupt trade and impact on all aspects of society. There is simply no way to mitigate every impact that no deal will have, no matter how hard we try.”

First Minister Nicola Sturgeon. Photo: Jane Barlow/PA Wire

It came as the Governor of the Bank of England stepped up his own warnings, despite criticism from Brexiteers, saying shoppers and motorists will face higher prices and a “substantial number” of firms could find they can no longer compete in the event of a no-deal Brexit.

Mark Carney insisted the challenges posed by no-deal should not be played down, responding to optimistic predictions from the Prime Minister by saying: “It may take a while to get to the sunlit uplands.”

His comments came after a leaked Government document suggested a no-deal Brexit could trigger “consumer panic”, food shortages and an increased security threat within a fortnight. The slide, prepared for ministers and obtained by Sky News, says the pound could fall in the first month, while Northern Ireland may face civil unrest.

Marked “official sensitive” and titled “What this could look like on the ground”, it also warns that UK nationals in the EU could lose access to services and residence rights within 24 hours.

The prediction of a further collapse in the value of sterling was echoed by Mr Carney, who said it would lead to increased prices for fuel and food.

He said a shift to World Trade Organisation tariffs would also render many firms – “potentially it’s a substantial number” – uneconomic, possibly resulting in closures and job losses.

Reports suggest the leaked slide was prepared in the final weeks of Theresa May’s tenure. It is understood the document was shown to ministers but not signed off by the Government, meaning it was not official policy.

Within 24 hours, it says cross-border agriculture trade in Northern Ireland “virtually stops”. Within a fortnight, it says: “Potential consumer panic and food shortages, even in areas which are not directly affected at the border.”

And it warns of a “possible increased risk of serious organised crime including people smuggling and illegal migration”.

The first month could also see pressures on policing becoming “unsustainable”, as operational gaps in security “continue to emerge”.

‘We can’t defend against every impact of no-deal’, Sturgeon warns