NICOLA Sturgeon has said a second referendum is at the “heart” of the general election, just a week after saying the outcome would not decide if Scotland becomes independent.

The First Minister said who had the final say on whether to hold another vote on the constitution - Holyrood or Westminster - was now a central part of the campaign.

Meeting voters with Alex Salmond in the Northeast, Ms Sturgeon said: “The issue at the heart of this election is, whether you support independence or oppose independence, surely that decision should be taken by people in Scotland, by the Scottish people and the Scottish Parliament, and not by a Tory government at Westminster.”

MSPs voted last month by 69-59 to request referendum powers from Westminster with a view to a referendum by spring 2019.

However Theresa May has said "now is not the time" given the UK's focus on Brexit.

Ms Sturgeon's statement was criticised by Unionist parties, who claimed she had been blowing hot and cold over independence for the past week, an indicator of anxiety in the SNP camp.

A recent poll has suggested the Scottish Tories could gain seven SNP seats in June with a strong pro-Union stand.

After Theresa May called the snap vote, Ms Sturgeon said a good result for the SNP would “reinforce” her mandate for a referendum, but last week in Aviemore said: “The election won’t decide whether or not Scotland becomes independent.”

Douglas Ross, the Tory candidate in Moray, said: “This time last week, Nicola Sturgeon insisted her campaign wasn't about independence. Now she says it's at the 'heart' of it. Her campaign is in chaos."

Visiting a nursery in Insch to highlight the SNP’s plan to double free childcare, Ms Sturgeon also said only SNP MPs could stop Mrs May having a “free hand to do whatever she wants" in government.

She said: “We know Theresa May wants a free hand to do whatever she wants. We've got to make sure that there's a check on the Tories, that there's strong opposition and strong voices for Scotland standing up for progressive policies like this one.”

The First Minister also said the Tories should “watch their language”, after Mrs May mentioned the SNP in the same breath as terrorists in a weekend speech in Aberdeenshire, saying there was a need to take action against "extremists who would divide us and... the separatists who want to break up our country".

Ms Sturgeon said: "It's fine to have a robust debate, that's what democracy and elections are all about, but using language that paints the SNP as something everybody knows we're not, I think, is irresponsible."

Labour’s James Kelly said: “Nicola Sturgeon has confirmed the worst kept secret in Scottish politics: this General Election is only about a divisive second independence referendum for the SNP. It's time for the Nationalists to focus on the job of governing.”

Scottish LibDem leader Willie Rennie added: “Clearly the First Minister is spooked by the upcoming general election; fearing that her neglect of the north east will come back to bite her.

“Despite her protestations that she wants to talk about other things, this admission from the First Minister will surprise no one.

“Sadly while she has been focused on independence, Scotland’s position in the international education rankings has plummeted and children have been waiting more than a year for mental health treatment.