FORMER SNP leader Gordon Wilson has warned his party not to join the main pro-EU campaign group Britain Stronger In Europe – claiming working with it could undermine the goal of achieving independence for Scotland.

Wilson spoke out after it was revealed at the weekend former Labour MP Frank Roy, who played a prominent role in the anti-independence Better Together campaign, has been appointed as campaign director for Scotland for the pro-EU organisation.

Kevin Pringle, the SNP’s former media director, will provide communications support to the group fighting for a vote to keep the UK in Europe.

Wilson told The National he had no objections to Pringle working for the group in a professional capacity, but would object to the SNP having a close involvement.

“Britain Stronger in Europe is very lucky that it has got the services of such a consummate professional in communications as Kevin Pringle. As a professional matter he must promote Britain in Europe, but the SNP should be very careful about getting involved in any pro-European Union group which seeks to promote a stronger Britain within Europe,” he said.

“What the SNP should do, if it is running a campaign on Europe, is to promote the idea that Scotland is stronger in Europe.”

He added that if the SNP joined Britain Stronger In Europe it could impact on the outcome of a second independence referendum campaign, weakening the possibility of a Yes vote.

“If you have a full scale campaign at UK level on Britain Stronger in Europe it will have a trail of propaganda which will be adverse to the concept of Scotland being stronger in Europe as an independent entity,” he said. “It could stiffen the sense of Britishness within Scotland and could persuade some people who might have been persuaded otherwise to harden their resolve [for Scotland] to stay in the UK.”

Opinion polls suggest the outcome of the ballot, which could take place as early as this summer, is on a knife-edge.

A poll by Survation last month showed 51 per cent of people across the UK want to leave the EU, while 49 per cent wish to stay. In Scotland the survey found 58 per cent want to stay, while 42 per cent want to leave.

An SNP spokesman said: “It is important there is a distinctive Scottish EU referendum campaign – and the SNP will play our part in it – with people from across civic Scotland, trade unions, businesses and political parties who want to remain.”

A ‘Stronger In’ spokesman said: “Stronger In is the UK-wide campaign making the case that we are stronger, safer and better off in Europe – reflecting the fact that this is a UK referendum – and in Scotland we are promoting the case for keeping the benefits of EU membership from a Scottish perspective.

“We welcome that there is likely to be a distinct SNP campaign seeking an In vote – and indeed campaigns from other parties – and look forward to working for the same result.”