SCOTLAND could block any future move by the UK Government to leave the European Union under moves being given to Holyrood for greater powers, according to a leading academic.

Dr Eve Hepburn has suggested in a submission to Holyrood’s Europe and External Relations Committee that greater responsibilities being given to Scotland under the devolution settlement would be undermined if the UK left the EU – and that the country would have an effective veto on any withdrawal.

The issue emerged as experts were called by MSPs to examine the implications for Scotland of the EU referendum, due to take place by the end of 2017.

Discussions at the committee yesterday centred on the different policies being pursued on immigration by the Westminster and Scottish governments. The former wants to restrict the number of migrants coming from Europe and bring in tough rules on them claiming benefits, while the latter wants to encourage more workers to come to Scotland.

Hepburn’s evidence argued that any move to leave the EU following a referendum could run contrary to powers relating to migrant rights given to Holyrood under the Scotland Bill.

She said: “There is an issue to consider of whether some of the demands that the UK government is making in its EU renegotiation efforts are actually incompatible with devolution as Scotland has some control over migrant rights – such as seeking to limit migrant access to social benefits, over which the Scottish Parliament may soon be gaining control.

“Indeed, these new Scottish powers may mean that [Prime Minister David] Cameron is able to negotiate restrictions on migrant access to benefits only in parts of the UK outside Scotland, as the UK Government is unable to legislate on Scottish matters.

“This links with a broader issue of whether the UK Government would actually be able to negotiate an exit from the EU, as this would directly affect Scotland’s competences as set out in the Scotland Act, which requires the UK to gain Scottish consent.”

She continued: “According to the evidence that Professor Douglas-Scott and I submitted to the Devolution (Further Powers) Committee, this would mean that if the UK proposed to radically alter its relationship with the EU – as is currently being proposed by the UK Government – then the Scottish Parliament could potentially veto any changes proposed by the UK Parliament that had a profound impact on its competences.”

Hepburn’s position appears to go further than the calls being made by First Minister Nicola Sturgeon for a “double lock” to ensure no exit from the EU can take place without a majority in all four nations of the UK agreeing to it.

In the run-up to the independence referendum, Alex Salmond said he wanted to attract 24,000 migrants to Scotland every year until 2030. However, the PM has set out a position with targets to reduce immigration and restrict EU migrants’ access to public services and benefits.

But at the committee yesterday another academic said he believed proposed legislation to devolve more power to Holyrood could be altered in order for Scotland to adopt a more pro-European immigration policy than the rest of the UK.

Dr Daniel Kenealy, a lecturer at the University of Edinburgh’s Academy of Government, said he believed the Scotland Bill would have to “evolve” to allow the Scottish Government to take a different approach to that south of the Border.

He said: “The way I read the Smith Commission, which is by no means the definitive reading of it, if a Scottish Government in the future wanted to give different benefits to EU migrants here, that were effectively denied to them for a certain period of time – four years has been mentioned by the Prime Minister – I think there would need to be amendments to the current draft legislation around Smith.

“Smith allows for the creation of new benefits in devolved areas, it allows for the top-up of non-devolved benefits, but this would be an issue of actually allowing access to benefits to people who in the UK system wouldn’t have that access for a certain number of years and to me that’s qualitatively different.

“Smith could evolve in a certain way that would allow the Scottish Government, or the Scottish Parliament, to do things differently but not, I don’t think, based on its current language. But that can change.”

A Scottish Government spokesman said: “The Scottish Government greatly values the contribution EU migrants make to our economy, society and communities. EU citizens exercising their Treaty Rights have a legitimate reason to be here and will always be welcomed. Studies have shown that EU migrants come to Scotland and the UK to work – not to claim welfare benefits.

“Meanwhile, the Scottish Government has made clear that we want Scotland to remain in the EU, and to play a fuller role in shaping reform and developing the European Union of the future.”