The SNP’s opposition to Brexit has “set a template for the unionists” to block independence, a former deputy leader of the party said today.

Jim Sillars said his party’s support for a second referendum on European Union membership would cause “a lot of complications and a lot of opportunity for Ruth Davidson to go and tell the Tory Prime Minister to make it as difficult as possible” for Scotland to separate from the UK.

Speaking at a Morning Star conference in Glasgow on Scotland’s future constitutional settlement, the former MP said: “The present conduct of the SNP and their anti-Brexit campaign has set a template for the unionists to stop us fulfilling a Yes vote.

“The moment you say that the question on the ballot paper that people voted on is not legitimate, then the unionists pocket that away.”

Mr Sillars also criticised Scottish Constitutional Relations Secretary Mike Russell for seemingly implying that Tory MPs who voted for Theresa May’s Brexit deal were traitors.

The SNP cabinet minister tweeted the 11 MPs’ names along with the hashtag #RagmanRoll, a reference to Scottish aristocrats who pledged allegiance to the English crown in the 13th century.

“In the highest reaches of the Scottish government there are those who imply their opponents on Brexit are traitors,” Mr Sillars said.

“And that shows a lamentable failure to exercise the personal constraints [sic] that should be practised by all leaders in a democracy.

“We have the right to think differently; it’s democracy’s foundation. And in the situation we’re in today, where the whole climate can be changed to a hateful climate, to use language like the Ragman Roll against those who don’t agree with them, actually, is an extremely dangerous thing.”

Mr Sillars argued that “even if there was an independence referendum and we won it on the Yes side,” it would not “be easy to get it” due to “what the SNP has done in its anti-Brexit campaign.”

He added: “So I don’t think that I can talk about the powers necessary in an independent Scotland, because I think that’s off the agenda for some time.”

Speaking at the same event, Labour councillor and parliamentary candidate Matt Kerr deplored the “tragic” failure of the Scottish parliament to assert itself as a force for innovative policy-making, adding: “There’s good people in there, but they’re caught up in a mass of managerialism.”

Mr Sillars went on to call for Scotland to take control of its offshore industry, exploiting undersea oil and gas reserves to the north of the country and in the Firth of Clyde and to not let the profits be sucked up by international conglomerates.

Labour peer Pauline Bryan stressed her party’s prioritisation of the green economy, which shadow chancellor John McDonnell said could create 50,000 new jobs north of the border under a Labour government.