Brexit has created the biggest democratic deficit in post-war Scotland, according to First Minister Nicola Sturgeon.

She said she had yet to hear any detail from the Tory leadership contestants about how they would leave the EU.

Speaking at Law Society of Scotland conference on two decades of devolution, the Scottish First Minister argued the actions of the UK Government since the Brexit referendum has left constitutional conventions “in shreds”.

Ms Sturgeon said: “Twenty years on from the establishment of our Parliament, we face the most important example of democratic deficit in Scotland’s post-war history.”

She claimed the UK Government had acted “in a way which pays little or no heed to Scotland’s wishes, priorities and values”.

Accusing the Tories of seeking to “deepen division rather than bring people together” in the wake of the EU referendum, she added the UK Government had “sought to interpret the result in the hardest way possible and red lines got drawn that didn’t have to be drawn”.

With just over four months until the UK’s renegotiated Brexit date, Ms Sturgeon said: “I haven’t heard any detail of anything that Jeremy Hunt or Boris Johnson has said about Brexit, how they’re going to deliver it by October 31 or how they’re going to renegotiate something that the EU has said is not up for renegotiation.

“But if the recent experience of the Scottish Government dealing with Tory politicians in Westminster is anything to go by, there’s not much of what they say is either deliverable or turns out to be delivered.”

Ms Sturgeon referenced the UK Government’s referral of the Continuity Bill and suggested it shows “an ongoing fear of devolution” and that relations between the UK and devolved administrations “simply cannot bear the weight of Brexit”.

Criticising the rejection of the Bill, which was approved by the Scottish Parliament, Ms Sturgeon added: “I think that the fact that is even legally possible is in itself quite remarkable but the fact that the UK Government has behaved in such a way is extraordinary.

“It leaves in shreds the supposed safeguards of constitutional convention, or proper behaviour, or indeed honourable conduct that is supposed to take the place of law in our constitution.”

Reiterating her case for Scottish independence, Ms Sturgeon argued it was “the best way of building a genuine partnership of equals in these islands.”

She said: “We know that our closest relationships will always be with our friends and neighbours in the United Kingdom so that willingness to co-operate will continue regardless of our future constitutional status but that co-operation – if it is to be effective – must be on the basis of mutual agreement and consent.

“Obviously I have no objections to people who are against independence, everybody who is against independence is absolutely entitled to argue that, whether that is Theresa May or David Cameron or Jeremy Hunt or Boris Johnson.

“Where I take issue is the idea that it is for them – or indeed for me – to decide Scotland’s future, it should be for the Scottish people to decide our future.”

Asked about whether there should be a threshold on any future referendum, Ms Sturgeon said: “I don’t take the view that that should be a requirement – the narrowness of the Brexit result absolutely has been a factor in what’s come since but I don’t think what has happened since the Brexit vote has been in any way inevitable.

“I think a basic tenet of democracy – how we take decisions – is by a majority vote.

“I don’t think that the mess that Brexit has become was inevitable, even with the narrowness of the result.”

Pamela Nash, chief executive of Scotland in Union, said: “The democratic deficit in Scotland is Nicola Sturgeon’s refusal to accept the democratic result of the ‘once in a lifetime’ independence referendum.

“She continues to ignore the majority of voters who want Scotland to remain part of the UK.

“Only a fifth of people in Scotland support her reckless plan for a divisive second independence referendum within two years.

“Nicola Sturgeon should stop provoking confrontation in Scotland and get on with the day job of running our schools, hospitals and public services.”