‘CRITICAL issues” around Scotland’s borders after independence are raised in a new report published on Thursday.

The 30-page paper says “political sensitivity” would be needed in the Scottish Borders,where voting trends suggest residents would be “least ­likely to back independence in a ­referendum”.

Authored by Professor Katy ­Hayward of Queen’s University ­Belfast and Professor Nicola ­McEwen of Edinburgh University, it argues that Brexit has “profoundly changed the context in which independence is contested and could be realised”.

And it questions how a new “EU border across Britain” would work as a result of the accession of a ­sovereign Scottish state to the bloc, which is the future the SNP and the Greens are looking to.

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It states: “Brexit has reenergised the campaign for Scottish ­independence, but it has made the practicalities of independence more complex. This is exemplified in the question of how Scotland would manage its borders as an independent nation-state and, potentially, as an EU member-state too.”

First Minister Nicola Sturgeon has repeatedly said that Brexit is a ­“material change in circumstances” and justifies a fresh constitutional ballot. Political opponents have ­argued that the disruption of Brexit proves the status quo must stand.

The National: 49_Dr_Katy_Hayward.

Professor Katy Hayward of Queen’s University Belfast is co-author of the new report

Writing for the UK In A ­Changing Europe think-tank, Hayward and McEwen say Scotland’s new relationship with England and Wales would be governed by the terms of the UK-EU Trade and Cooperation ­Agreement (TCA), which could be “very different” from that in place ­today and would determined the shape of a new border arrangement. TCA rules on customs declarations and checks would mean logistical and security challenges and there would be “no automatic retention of free movement of services, ­capital or ­(increasingly) digital data ­between Scotland and the rest of Britain, ­because these policy arenas are ­becoming ever more subject to the competence of the EU”.

However, they say a fully-oper­ational Northern Ireland Protocol would mean border controls would not be necessary between Scotland and Northern Ireland and that the overall “scale and nature of the ­border challenges for Scotland would be quite different” to those resulting from the Northern Ireland Protocol because, from outwith the UK, the country would not have to manage membership of two diverging regulatory markets and customs regimes.

On trade with the rest of the UK, which in 2019 made up £52 billion worth of its £87.1bn total exports, the authors cite the experience of Ireland.

More than half of all Irish ­exports (55%) went to the UK when those states joined the European ­Community in 1973. However, that had ­decreased to just 9% by 2020. And they suggest sealing lorry loads of goods at the Scotland-England ­border and preventing further pick-ups on the journey through England to France could simplify deliveries.

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It’s further argued that though there would be costs and other ­challenges in setting up a new border regime, “assuming responsibility for managing an EU border across Britain need not preclude cross-border ­cooperation, including in areas like policing, criminal justice and ­security, where EU competence is more limited”. “Indeed, effective management of the border would be supported ­considerably by ­cooperation between ­authorities on either side of it.”

On the implications for residents of the Scottish Borders, the authors said a change in rules on crossing to England could impact on a sense of identity or work and leisure opportunities.

They said: “A ‘harder’ or less open border can have social and psychological consequences as well as economic, legal and political ones. Trends in voter preferences suggest that the Scottish Borders may be the area of Scotland that is least likely to back independence in a referendum. This underlines the need for political sensitivity and care in the process of delineating and introducing any new border management measures.”

And they wrote: “Any detailed prospectus or white paper intended to instil confidence in a transition to independence should confront the challenges Brexit has presented for managing Scotland’s borders.”