A former SNP deputy leader has called for a Leave vote in the EU referendum to end ‘open door immigration'.

Jim Sillars, who served as senior vice convenor from 1991-1992, said an independent Scotland should reject the free movement principle, describing it as not "sensible".

His comments came in a pamphlet, The Logical Case: Why ScotLeave.EU Makes the Most Sense, which was published on Thursday.

The veteran nationalist said: “An open door, which means no one knows how many people will come, makes for serious difficulties in planning health care, education, assessing and meeting housing needs.

“That is why Canada, for example, to where Scots could freely migrate in years gone by, now has a system that welcomes migrants, but controls the numbers in accordance with its ability.”

Sillars, who has encouraged SNP supporters to back left-wing coalition Rise on the regional list in May’s Holyrood election, insists the current free movement of people inside the EU has led to the exploitation of workers.

He claims: “Employers like the open door, because if many more workers come on to the labour market, then local workers can be exploited with lower wages and so can incoming workers.”

Figures from the Office of National Statistics show that in 2014, 173,000 people who live in Scotland were born in a European Union country other than the UK.

Scotland’s Future, the SNP’s white paper on independence, pledged the Scottish Government would “do more to encourage young people to build their lives and careers within Scotland to attract people to live in Scotland.”

The independence blueprint also argued that Scotland had a distinct need for further immigration to tackle the economic issues faced by an increasingly older population.

Jim Sillars was a leading architect of the SNP’s “independence in Europe” platform, which shifted the party from Euroscepticism to support for what was then the European Economic Community. Sillars lobbied for the U-turn in his 1985 pamphlet Moving On and Moving Up in Europe and his book The Case for Optimism the following year. Sillars posited that endorsing "an independent Scotland within the Community” would mean "the charge of separatism disappears”.

SNP MSP Christina McKelvie, who chairs the Scottish Parliament’s European and external affairs committee, said: “The SNP will make the positive, progressive case for Scotland, and the UK, to remain part of the EU – this includes the right to live, work and study across Europe, which we believe is an important benefit of EU membership.

“Not only has free movement created opportunities for 2 million UK citizens who live in other EU countries but we believe that the 170,000 EU nationals who live in Scotland enrich our culture, strengthen our society and contribute significantly to our economy.”

A 2015 YouGov poll found 49% of Scots wanted to reduce the level of immigration into the UK, compared to 5% who wished to see it rise. Around a quarter of the country said inward migration should be kept at current levels while 15% wanted an immediate halt.

Report by Aidan Kerr, STV’s digital politics reporter. You can contact him at aidan.kerr@stv.tv.