A UK exit from the European Union would put Scotland in a “very, very difficult position” – with “no best scenario” in constitutional terms – a leading economist has warned.

Brian Ashcroft, emeritus professor of economics at Strathclyde University, highlighted his view that leaving the EU would cause significant damage to the Scottish economy.

However, he saw no “immediate argument” in the event of Brexit that Scotland would be better to become independent so it could try to get back into the EU. He warned that, in such a scenario, economic gains from being part of the EU would be offset by loss of UK trade.

Mr Ashcroft, who was presenting the latest economic commentary from Strathclyde University’s highly-regarded Fraser of Allander Institute, said of the prospect of a Brexit vote: “It would put Scotland in a very difficult position. Frying pans and fires come to mind. There is no best scenario for Scotland in that scenario.”

He warned Scotland would suffer in terms of inward investment and international trade if the UK were to leave the EU.

Fraser of Allander meanwhile warned Scotland may in any case fail to avoid a recession in the current quarter, after a “hair’s breadth” escape from such a scenario last year. The Scottish economy achieved marginal growth of 0.2 per cent in the fourth quarter, after contracting by 0.1 per cent in the previous three months.

The think-tank sounded the warning as it cut its forecast of Scottish growth this year from the 1.9 per cent it predicted in March to 1.4 per cent. It reduced its projection of growth in 2017 from 2.2 per cent to 1.9 per cent. Fraser of Allander forecasts expansion of two per cent in 2018.

Mr Ashcroft emphasised these forecasts assumed a vote for the UK to remain in the EU, and signalled Fraser of Allander would likely cut its Scottish growth projections in the event of a vote for Brexit.

Fraser of Allander warned Brexit would pose a “real threat” to Scotland’s future growth.

Opinion polls signal next Thursday’s vote on EU membership will be close. Meanwhile, opinion polls and betting odds suggest a significant possibility that the Scottish electorate could vote unsuccessfully to stay in the EU.

Asked if he expected there would be a clamour for a second referendum on Scottish independence in the event of a UK vote to leave the EU, Mr Ashcroft replied: “All I can say, from the economics point of view, [is] the fact Britain might leave the EU puts Scotland in a very, very difficult position economically.

“Even though we identified these clearly negative impacts on Scotland from Brexit, to…decouple from England, when more than two-thirds of our trade is with [the rest of the UK], would still be a major problem.”

He also cited Scotland’s “relative fiscal balance”, amid weakness in the oil sector.

Mr Ashcroft said: “I don’t think, for Scotland, there is any immediate argument that we would be better leaving the Union, and going to the EU. The gains we would have from going back into the EU would be offset by the losses from breaking the trade links with the rest of the United Kingdom.”

Emphasising the likely impact of EU exit on inward investment, he highlighted the fact that overseas companies set up operations in Scotland to gain access to the EU free trade bloc.

Mr Ashcroft said: “In Scotland, we are a major recipient of inward investment. It is hard to see that would continue to the same degree once we are outside the EU because large amounts of that investment [are based on] trade with the EU. Why should they [overseas investors] come here when we have erected a barrier?”

He also warned of a danger of stagflation in the UK, for the first time in many years, in the event of a vote to leave the EU. He cited potential for a sharp fall in the pound and a consequent rise in import prices, pushing up overall consumer prices index inflation, coupled with a drag on output arising from a detrimental impact on the UK’s overseas trade.

Signalling Fraser of Allander would likely cut Scottish growth forecasts for 2016 and future years in the event of a vote to leave the EU, Mr Ashcroft said: “We are not very sanguine at all in the short, medium and long term [about] a Brexit. I think we probably would…be coming out with new forecasts. We are discussing the transmission mechanisms.”

He highlighted the complexity of working out the “animal spirits” effect, in terms of uncertainty and the impact on confidence.

Paul Brewer, partner at Fraser of Allander commentary sponsor PricewaterhouseCoopers, highlighted the impact that uncertainty ahead of the EU referendum was having in terms of dampening investment in the likes of property.

Touching on the opinion polls and companies’ behaviour, he said: “It is interesting in the last three months it has turned from hypothetical into quite tangible.”

He cited “a lot of decisions not to do things until there is more clarity”.

Mr Brewer added: “Clearly a Brexit vote is not clarity, so that could continue for some time.”

Fraser of Allander highlighted the significantly weaker performance of the labour market in Scotland, compared with that in the UK as a whole, since 2008.

Flagging the current recession risk, Mr Ashcroft said: “There is a strong risk that the first quarter [of 2016] might be negative.”

While noting signs from the likes of the labour market that the Scottish economy appeared a little stronger in current quarter, he warned there was still a “risk” of a fall in output in the three months to June. Recession is defined as two consecutive quarters of contraction.