A LEADING SNP activist who could become Nicola Sturgeon’s deputy this summer has insisted there will be a second independence referendum within the next three years.

Julie Hepburn, who is standing to succeed Angus Robertson in the party’s depute leadership contest, said she is in no doubt there will be a new vote within the current Scottish parliamentary term which ends in 2021.

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In an interview with The National she underlined a mandate given to the SNP in the last Holyrood election to hold a new referendum if Scotland voted to remain in the EU and the UK voted to leave.

“It is very clear we have a mandate to hold a referendum before 2021, so I don’t doubt we will hold a referendum. We have a mandate now to hold a referendum and I cannot see us letting it slide away,” she said.

It is the first time Hepburn has set out what she believes will be the timescale for a new vote on independence, an issue which has dominated the internal election. Until now she has declined to give her views on the matter, saying it is an issue for the First Minister and Scottish Government to determine.

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Her intervention has particular weight as she is close to senior figures in the party, having worked alongside Peter Murrell, the party’s chief executive, and husband of the First Minister, the Depute First Minister John Swinney and the long-serving MP Pete Wishart.

Hepburn also told The National that if she became the next depute leader, the first major thing she would do would be to call on the party’s ruling body, the National Executive Committee, to launch a new independence campaign in a bid to increase levels of support for the goal which currently sits around 45 per cent.

“I personally would like to see a new campaign start very soon. There has been a hesitance of people waiting for a referendum,” she said. “It’s about making clear we are campaigning for independence, we are continually campaigning for independence and we need to lay those foundations, so as soon as we have a date we have already laid those foundations. Arguably that referendum will come about a lot quicker if we are out having those conversations, particularly with No voters, and we are able to demonstrate there is a shift towards independence.”

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Hepburn said all 500 of the party’s elected MPs, MSPs, MEPs and councillors should be out knocking on doors and speaking to voters and listening to No voters over the summer. “We are in a very good position to win a majority for independence and over the summer I think we should be listening to people. Every one of our 500 elected representatives should have a target to have 100 conversations with people over the summer,” she said.

Hepburn is one of three candidates standing in the contest. Economy Secretary Keith Brown is the frontrunner with considerable backing from MSPs while Chris McEleny, the SNP group leader on Inverclyde Council, is pitching himself as the candidate who can speak for the left of the party.

Hepburn has been endorsed by a number of senior figures too including the MSP Sandra White and MP Alison Thewliss. The winner will be announced in June.

Hepburn is also being backed by Malcolm Fleming, a former special advisor to the First Minister and her predecessor Alex Salmond.

He said: “Julie isn’t only a dedicated and extremely hard-working SNP activist, with a huge amount of campaigning experience. Crucially, she also brings a nationwide perspective and a strong focus on the organisational needs of the party which I believe will help us win independence.”