Leaked government analysis suggests the majority of regions in the UK will suffer major blows to their economy in any post-Brexit scenario.
The figures, which form part of the controversial EU Exit Analysis - Cross Whitehall Briefing document leaked to Buzzfeed last week, suggest that places such as the North East, West Midlands and North West will suffer double-digit drops in their local economy in the event of a no deal, down 16 per cent, 13 per cent and 12 per cent respectively. Northern Ireland will also suffer a 12 per cent hit.
London weathers the storm best, with the local economy falling two per cent if we strike a free trade deal and 3.5 per cent with no deal.
The figures, which have been published by Sky and the BBC among others, apply over 15 years.
A Number 10 spokesman pointed to previous comments made by the Prime Minister, in which she insisted the analysis did not represent the UK government's preferred model. He declined to comment further.
Publication of the national GDP predictions last week triggered an almighty row in Westminster, with Brexit-backing MPs dismissing the forecasts.
But the figures have been circulating amongst MPs, prompting SNP's Stephen Gethins to quiz Northern Ireland secretary Karen Bradley over the matter.
"Government analysis suggests that Northern Ireland could be cost up to 12 per cent of its GDP. Does she believe any analysis she has seen? And is this too high a price to pay to stop a Tory civil war breaking out?" he said.
Bradley replied that the "DexEU secretary [David Davis] has dealt with the issues surrounding the leaked report".
"It is important to state that the UK government wants to achieve a good deal for the UK that protects the economic integrity of the UK," she added.
MEP Seb Dance said it was "cynicism of the worst kind to pretend this is what people voted for."