THE border between an independent Scotland and England could suffer major tailbacks at checkpoints, a leading academic has warned Angus Robertson at the SNP conference.

Professor Nicola McEwen told the Constitution Secretary that “an awful lot of traffic” would have to pass through “not many crossing points” after a Yes vote.

“There would inevitably be pressures on trade crossing that border,” she said. 

Prof McEwen, the co-director of the Centre on Constitutional Change, who has studied the implications of independence for the border, was speaking at a fringe meeting sponsored by the IPPR thinktank and the UK in a Changing Europe.

Another academic at the event also dashed Nationalist hopes the EU would treat an independent Scotland as generously as it did Northern Ireland after Brexit.

Anand Menon, director of UK in a Changing Europe, warned the EU had created a special protocol for the region because of its unique political history and the peace process.

It would not do the same for Scotland, he said, also predicting the UK Government would not want to negotiate a generous deal with Scotland in case it inspired Irish unification.

Mr Robertson said he wanted to look at the positive aspects of the issue.

Under the SNP’s plans, an independent Scotland would join the European Union, meaning its border with post-Brexit England would become a tightly regulated EU land border.

Prof McEwen said: “That creates challenges, that creates responsibilities and obligations on the part of the Scottish Government.

“If Scotland becomes independent in the EU, there is an obligation to manage that border,  to ensure that things crossing the border, entering the EU via that border, are eligible to enter, are eligible to trade within the EU single market. 

“So there is no getting away from the fact that there would have to be border checks. 

“And what does that mean, in practice? It means at-the-border checks. 

“You’re talking about 154 kilometres, 25 crossing routes roughly, mostly minor routes, one major trunk road Glasgow to Carlisle, three others that are fairly major crossings. 

“So in terms of a technological and physical challenge, it's not an insurmountable one. 

“On the other hand, it's an awful lot of traffic to go through a novel to go through not very many crossing points. 

“So there would inevitably be pressures on trade crossing that border.” 

She said there would also be more paperwork in offices and specialist logistics firms.

She said: “So it's the bureaucracy and the expertise that surrounds that and getting the processes straight to facilitate that kind of trade across borders would be really, really important and could minimise the effect and the requirements that take place at the physical border itself.” 

However she said she was as confident as it was possible to be that there would not be passport checks as maintaining the Common Travel Area was also wanted by Ireland.  

She said the border challenges would be directly affected by EU-UK relations, with the problems getting tougher the more the UK moved away from EU rules.

Mr Robertson acknowledged Brexit had made the debate around an independent Scotland in Europe “very different” from 2014, as the border with England would be an EU one too.

However he noted Prof McEwen had said the challenges were not insurmountable.

He said more detail would be provided in future papers in the Scottish Government’s prospectus for independence, Building a New Scotland. 

He said: “Yes, we will need to find technical solutions, including areas where there are significant areas of technical arrangements that need to be made. 

“This is not an insurmountable challenge. No, it's not. And as far as I'm concerned, let's get on with it as quickly as we can.”

In June, SNP president Michael Russell suggested the Northern Ireland Protocol could be a model for a “seamless” Scottish-English trade border.

He said: “There is a seamless border on the island of Ireland. Goods going across, it still seems (like) it’s a minor matter in terms of what exists elsewhere. I think there is every prospect of being able to enjoy a good and even better trading relationship.”

However Professor Menon warned not to draw the “wrong lessons” from Brexit.

He said: “It's very easy to talk and to think about what's happened with Northern Ireland as a model for what might happen with Scotland.

“The European Union, for all the rhetoric, has been massively flexible about Northern Ireland, it’s given Northern Ireland a position that would not give any other territory in the world. That I think is due to the specifics of Northern Ireland.

“It's due to the history of violence on the island. It's due to the Good Friday Agreement. And crucially, it is due to the fact that Northern Ireland engages the vital interests of an existing member state.

“It would be rash, I think, to assume that the European Union will be willing to show the same degree of flexibility to Scottish borders,because none of those three conditions apply.” 

Mr Robertson later flatly rejected an independent Scotland joining the European Free Trade Association (EFTA) instead of the EU, as advocated by former SNP minister Alex Neil.

EFTA’s four members - Norway, Iceland, Liechtenstein and Switzerland - are in the European single market and must abide by its rules, but have no part in deciding them.

He said: “I'm not in favour of Scotland being a rule taker, as EFTA members are, where they have to incorporate European legislation without being part of the process of making that legislation. That's the beginning and the end of my thinking about that. 

“There are very specific reasons why the EFTA member states are where they are. 

“But I don't think that's the right course of action for Scotland to emulate.

“ I think we need to be in and about the rules as they're been developed, in and about the legislation as it's been developed. 

“Being a member state of the European Union involves nominating a Commissioner, it involves having a permanent seat on the Council of Ministers, it involves being in the European Parliament, and in all of these three institutions. 

“We would have direct representation, and then of course there would be Scottish representation on the European Court of Justice. 

“So we will be fully part of the rulemaking but also the interpretation of those rules. That's why being a member state is a thoroughly good thing.”

Professors McEwen and Menon also said EFTA would be problematic.