According to KPMG’s latest quarterly Economic Outlook, a disorderly exit from the European Union on 31 October could prompt a four-quarter recession with GDP contracting by 1.5% next year.

However, a Brexit deal which finally resolves some of the uncertainties about the UK’s future trading relationship with the EU, could lead the UK economic to perform better in 2020 than previously expected (upgraded by 0.2% to 1.5% since the publication of KPMG’s last Outlook). This is despite constraints such as a slowing global economy.

Catherine Burnet, senior partner at KPMG in Scotland, said: “Our latest report is already identifying weaknesses in important sectors for the Scottish economy, including manufacturing, and services. In other areas, including retail, the downward trend has slowed, but the long term outlook remains concerning.

“It reaffirms the need for Scotland’s businesses to plan now, if they haven’t already developed a strategy. At KPMG, our work with the CBI on tackling productivity in Scotland is an example of some of the areas where greater collaboration can help the wider business community strengthen itself ahead of any significant future challenge. The threat of a no-deal Brexit has becoming increasingly real, as has the possibility of domestic political and policy change.”

Yael Selfin, chief economist at KPMG UK, added: “With the Brexit debate poised on a knife-edge, the UK economy is now at a crossroads. It is difficult to think of another time when the UK has been on the verge of two economic outturns that are so different, but the impact of a no-deal Brexit should not be underestimated.

“Despite headwinds such as the slowing global economy and limited domestic capacity, the UK economy now has the potential to strengthen over the next 12 months. But a no-deal Brexit could put paid to this upside, triggering the UK’s first recession for a decade.”

According to the Outlook, a deal could prompt an appreciation of the pound by as much as 15% and enable businesses to recommence their investment plans. With a strong labour market providing support for further consumer spending, the UK economy has the potential to then perform more strongly in 2020, even though a Brexit deal is unlikely to resolve all the outstanding questions about the UK’s ongoing relationship with the EU.

Conversely, the analysis suggests a no-deal Brexit could significantly dent exports in 2020 amid delays at the border and confusion over regulation. While both the Bank of England and the UK Government would be likely to offer monetary and fiscal policy support, their headroom for action is limited. Household sentiment would also undoubtedly suffer, hitting consumer spending, which has been so important to the UK economy over the past year, while business investment would remain depressed.

Ms Selfin added: “A no-deal Brexit would be a leap into the unknown for the UK economy and the consequences are therefore unpredictable, but even the foreseeable downside risks from no deal are substantial.

“By contrast, a last-minute Brexit deal and a transition period as the UK leaves the EU would give the UK economy some breathing space, enabling businesses to restart investment plans and pave the way for stronger growth.”