Plans by Scottish nationalists to win control over immigration policy north of the border would leave a "wide open barn door to England", MigrationWatch UK predicted.

The SNP has said it wants to relax many aspects of border control to boost Scotland’s working population and economy, and is expected to use a potential coalition deal with Labour to achieve a devolved immigration policy.

But in a new analysis MigrationWatch predicted migrants who entered Scotland under more lax controls devised by the SNP would come south into England.

Immigration levels across the Union would “spiral out of control”, the think-tank said.

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Lord Green of Deddington, the chairman of MigrationWatch, said: “An attempt at a looser regime in Scotland would quickly run out of control to the serious detriment of England.

“So long as we are one country there can be only one immigration regime.

“One of Labour’s five pledges is to ‘control immigration’.

“That would be destroyed at a stroke if Labour did a deal with the SNP on immigration.”

MigrationWatch said that so far nine out of 10 migrants have chosen to live in England, with a majority in London and the South East, and this would be unlikely to change under an SNP-Labour deal.

A White Paper produced by the SNP-run Scottish Government last July set out how it aimed to increase Scotland’s working age population to promote economic growth.

The Scottish Government paper described Westminster’s policy as “an aggressive approach to immigration, asylum seekers and refugees” and said that under devolved powers it would “welcome people who want to come to work and live in Scotland”.

It would introduce a points-based immigration system “targeted at particular Scottish requirements” and set up a more relaxed asylum system, closing Scotland’s only immigration detention centre.

The Scottish Government document also said it would re-introduce measures allowing students to work after completing their courses and lower the thresholds for family reunion visas.

MigrationWatch said the SNP’s proposals “look relatively harmless at first glance” but amounted to a “much looser immigration regime”.

“It was exactly apparently minor measures of this kind under the labour government that caused net migration to the UK to spiral out of control,” said the MigrationWatch report.

“This is particularly likely to be the case for Scotland when, in the absence of any border controls, migrants would be free to move south to where there are usually more jobs, higher pay, large communities of migrants and a better climate.”

It added: “While there is an open border with England it is extremely likely that the most qualified immigrants will leave for England at the first opportunity.

“The result would be a wide open barn door to England with very little benefit to Scotland.”

Any attempt to set up a regional immigration zone for Scotland, meaning immigrants were supposed to remain north of the border, was likely to fail, the report said.

A similar system in Quebec, Canada, had been largely abused, it noted.

Source: the Telegraph