The UK Government would face pressures to ensure there is not an “overly hard” border with Scotland after independence, according to experts.

The trade and cultural ties between the nations mean there is little reason why the rest of the UK would not want to support a continuation of that, an online seminar heard. However, the experts cautioned the politics of post-independence relations and how “bitter” the separation of the Union has been could shape the direction taken.

The comments came during an online discussion of an extensive paper examining the issue of borders after Scottish independence, published by think tank The UK in a Changing Europe.

It has outlined the challenges posed by the English border post-Brexit if an independent Scotland join the EU and warned they should not be downplayed.

Report co-author professor Nicola McEwen, senior fellow at UK in a Changing Europe, said it was a “given” Scotland would seek to be part of the Common Travel Area with the British and Irish islands.

The National: Nicole McEwenNicole McEwen

She said there would be no reason why a UK Government would not want that to happen and it could be negotiated as part of EU succession.

She added: “One of things I would mention is what is in the UK Government’s interests – that might be shaped by the politics of independence, how bitter things are, how the relationship is between the two administrations.

“But the rest of the UK trades with Scotland too. The rest of the UK population moves freely within Scotland too. So there would be interests and pressures coming from that side to try to ensure there wasn’t an overly hard border that would affect the interests of businesses on the other side of the border as well.”

Graeme Roy, professor of economics at Glasgow University, said there was no reason from an economic point of view why the UK wouldn’t want to have a “constructive” relationship with an independent Scotland.

“Obviously freedom of movement and the common travel area is absolutely crucial to that as well,” he said.

“One thing we know from economic history is persistence is a really strong effect here – there are cultural ties, there are family ties – these are all things that bind together.

“So you might have a change of political borders and international boundaries, but these remain – and these are really powerful and they last for a long time.

“There is nothing to suggest why the rest of the UK would want to deliberately not support that – but there is a lot of politics in that.”

However professor Katy Hayward, senior fellow at UK in a Changing Europe, cautioned there were limitations to the Common Travel Area.

“Before Brexit there was a lot of focus on the Common Travel Area and pointing to it and saying well you don’t need to worry so much about the Irish border because of the existence of the Common Travel Area,” she said.

“Of course we know the limitations of the Common Travel Area in terms of who it applies to, but also how it lacks a strong legal underpinning.

“Certainly it pre-dated the EU membership – and the EU membership went considerably further than the Common Travel Area did in terms of rights to work and study.”

She added: “The limitations of the Common Travel Area are being exposed by Brexit and they would perhaps be further exposed perhaps by Scottish independence.

“There would be hope, I think, there would much more strong legal foundations by that point.”