THE SNP’s much-vaunted summer initiative on independence was dreamed up by one of Nicola Sturgeon’s advisers at just a few hours’ notice, the Sunday Herald has learned.

The idea, which has led to a frenzy of speculation about a second referendum, was inserted in one of the First Minister’s conference speeches the “night before” she gave it.

A senior party source, one of Sturgeon’s inner circle, said it was only meant as an “applause point”, and the SNP leadership never anticipated the wild reaction it provoked.

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The source said the idea came from Sturgeon’s long-standing and trusted aide, Noel Dolan. He was Sturgeon’s senior special adviser in government from 2007 until 2014, when she was deputy first minister, then from 2014 until this May when she was First Minister.

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His responsibilities included policy advice and preparation for First Minister’s Questions.

The SNP last night said the initiative would start before Holyrood resumes in September, but refused to give any details of what it would involve. Opposition parties claimed the “haphazard” origin of the scheme typified the SNP’s sloppy approach.

A second SNP source added: “This shows the complete lack of preparation in it all. It was always dodgy given the EU referendum timetable. These gimmicks just are not clever.”

Sturgeon announced the initiative at the SNP’s spring conference in March. Describing the need to convince No voters to switch sides, she said: “This summer the SNP will embark on a new initiative to build support for independence.

“We will listen to what you have to say. We will hear your concerns and address your questions – and in the process we will be prepared to challenge some of our own answers.”

The rhetorical flourish prompted a huge round of applause from delegates, but also raised expectations sky-high about a concerted push for a second referendum.

However, the party has still not published any details.

In the absence of SNP activity, the Scottish Greens and local Yes groups have stepped up to fill the vacuum with their own campaigns.

Unionist parties urged the SNP to scrap the idea outright.

Deputy Scottish Tory leader Jackson Carlaw said: “The haphazard approach of Nicola Sturgeon’s speech-writing perhaps explains why, despite waiting for her fresh arguments with baited breath, we’ve seen nothing of this independence drive over the summer, just the same old tried and failed clichés.

“It’s typical SNP – say anything to get applause from the party faithful. But this tactic will always catch up on nationalists, as it appears to have done again.”

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LibDem MSP Mike Rumbles added: “This is not the first time an SNP First Minister has made empty claims about independence with no substance to back them up. A throwaway line led to weeks of speculation at a time when we should have been thinking about the future of public services like our NHS.

“This election was the first time that Scots were being asked to think about how we should use the new tax powers coming to Holyrood. Instead of offering proper policies, it seems the SNP were more concerned with clap lines on independence to keep the party faithful happy.”

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An SNP spokesman said: “The SNP has campaigned for independence throughout our entire existence and continues to do so.

“Obviously, the plans for our new initiative on independence have had to take account of the EU referendum outcome - however, our campaign will be launched before the end of the summer recess and we look forward to working with others across the Yes movement to build majority support for independence.”