NICOLA Sturgeon will need Westminster co-operation to hold a second independence referendum, ministers have confirmed.

A draft referendum bill, published this morning, show that a Section 30 order temporarily transferring legal powers to Holyrood would be sought if the legislation is introduced at the Scottish Parliament.

In a pre-amble to a consultation accompanying the draft bill, the Scottish Government states that it would be "expected" that a Section 30 order would be granted, as it was ahead of the 2014 vote.

Nicola Sturgeon has said previously that it is "inconceivable" that Theresa May would block a vote. However, other SNP figures including former justice secretary Kenny MacAskill have said it is "perfectly feasible" that Number 10 will refuse to grant the powers. The UK Government has not yet given a definitive answer to the question.

It is proposed at this stage that the same question as in 2014, 'should Scotland be an independent country?' would be used in a second referendum although a variation has not been ruled out following the consultation. Scotland's constitutional future would be decided by a simple majority, with no minimum turnout threshold.

As in 2014, 16 and 17-year-olds would be eligible to vote, as would EU citizens. Minor changes to 2014 are proposed around absent voting arrangements, permitted participants and appointment of polling and count staff.

The consultation asks about technical aspects of the bill, not whether a repeat referendum should be held.

Ms Sturgeon has said she will move for a second referendum if she concludes independence is the best or only way to protect Scotland's interests, following the UK's decision to quit the EU.

In June, 62 per cent of voters opted to remain, in contrast to 52 per cent who backed Brexit UK-wide.

The First Minister, in the foreword to the consultation document, said that the SNP has been elected on a "clear mandate" that Holyrood should have the right to hold a referendum, if there was a "significant and material change in circumstances" to 2014 such as Scotland being taken out of the EU against its will.

She added: "Scotland is now faced with one of the specific scenarios in which this government pledged that the Scottish Parliament should have the right to hold an independence referendum.

"The UK Government’s recent statements on its approach to leaving the EU raise serious concerns for the Scottish Government. We face unacceptable risks to our democratic, economic and social interests and to the right of the Scottish Parliament to have its say.

"Indeed those statements contradict the assurances given before the independence referendum in 2014 that Scotland is an equal partner within the UK and that a vote against independence would secure our EU membership.

"For many people, this approach will be evidence of a wider democratic deficit within the UK, where decisions about Scotland are too often taken against the wishes of people who live here."

She added: "This government remains willing to work with the UK Government to negotiate a future relationship with Europe that is in line with the views of the overwhelming majority of the Scottish people and which works for the United Kingdom as a whole.

"We will put forward constructive proposals that will both protect Scotland’s interests and give an opportunity for the UK Government to demonstrate that Scotland is indeed an equal partner.

"But if it becomes clear that it is only through independence that Scotland’s interests can be protected, then the people of Scotland must have the ability to reconsider that question, and to do so before the UK leaves the EU."