The Conservatives will only have a mandate to take Scotland out of the EU if they win the general election in Scotland, Nicola Sturgeon has claimed.

The First Minister indicated Boris Johnson's party would have to beat the SNP north of the border for her to accept the PM's Brexit deal.

Speaking in an election special on STV's Scotland Tonight, she said if the Tories managed to win the most seats in Scotland "they can claim what they want" in terms of a mandate from Scots.

But the SNP leader added that if the Conservatives cannot win in Scotland, taking the country out of the EU would go "against our will".

Sturgeon is the last of six politicians to be quizzed on the programme by STV's political editor Colin Mackay ahead of the December 12 general election.

In a wide-ranging interview, the FM was also pressed on her plan B for how to get a second independence referendum, on whether or not independence would result in more austerity and on her government's health and education record.

Sturgeon said that while she believes a win in the election in Scotland will strengthen her mandate for indyref2, the result in a week's time would "not settle the question of whether or not Scotland is independent".

But she added: "It will send a clear message that Westminster should not be deciding our future and the direction we take as a country. That should be for the people of Scotland."

Asked if a Conservative UK majority would in turn give the Prime Minister a mandate to deliver his Brexit deal, Sturgeon answered: "If you want to take Scotland out of the EU then you have to win the election in Scotland, otherwise you're doing that against our will.

"If the Tories win the election in Scotland then they can claim what they want in terms of what that entitles them to do but they have to win the election first."

She added: "Boris Johnson getting a majority in this election is not an inevitability and actually if people in Scotland want to stop it, then they have to vote SNP.

"In the Tory seats, we're the challenger.

"Everybody knows Labour's not strong enough to beat the Tories in Scotland and the last time the Liberal Democrats got anywhere near power, they put the Tories into government."

The First Minister wants to hold a second independence referendum in the latter half of 2020, but she faces a substantial roadblock in the form of the main UK parties.

Every one of them has said they would not sanction a transfer of Section 30 powers to hold a referendum - as was granted for the 2014 vote - within the time-frame Sturgeon desires.

Jeremy Corbyn has said he would not grant a request for referendum powers in "the early years" of a Labour government.

Asked if she could compromise on timing for the vote, the SNP leader said: "The principle is that it should be for the Scottish people, through their democratically-elected Scottish Parliament, to decide if there is a Scottish independence referendum and what the timing of that should be.

"It shouldn't be for Westminster politicians."

Yet the SNP's general election manifesto states there are "alternatives" to a Section 30 order for holding an independence vote.

Pressed on what those were, Sturgeon suggested primary legislation could be passed by MPs at Westminster to make such a referendum lawful.

"But the Section 30 order is how we did it in 2014 and a Section 30 order is how I think we should do it again," she insisted.

A study by the Institute for Fiscal Studies (IFS) this week indicated that if the SNP's election manifesto pledges were introduced in an independent Scotland, it could lead to more austerity.

The IFS previously judged that both Conservative and Labour pledges at this general election are "not deliverable".

Sturgeon said the IFS figures on the SNP were based in part on last year's findings of the growth commission - set up by her government - which said an independent Scotland would "start life with a significant budget deficit".

She continued: "The growth commission estimated a deficit in 20/21 for Scotland that is higher than it actually is in reality.

"The deficit is lower than it estimated for 20/21 because our onshore revenues have been growing faster than the rest of the UK.

"The risk to that economic prosperity is Brexit and in terms of the growth commission, it recommends continued increases in public spending.

"In fact, if the growth commission recommendations had been applied over the past ten years, we wouldn't have had the Tory austerity that's leading to Scotland's budget being £1.5bn lower next year than at the start of the decade."

Moving on to the Scottish Government's domestic record, the FM was challenged on the state of health and education in Scotland.

It comes after this week's international PISA study which found children in Scotland have fallen behind on maths and science compared to other countries.

She said governments "everywhere face challenges".

Sturgeon continued: "We recognised after the last PISA study there was a particular issue we needed to tackle as a priority on literacy and reading.

"The PISA study this week showed a significant improvement in reading performance.

"The independent statisticians say that maths and science is stable.

"That's not good enough in my view, so we'll continue with the focus to improve maths and science."

You can watch the full interview with Nicola Sturgeon on Scotland Tonight at the later time of 11.10pm on Thursday.

It follows Tuesday night's debate on STV featuring the four main Scottish party leaders.