The First Minister said full devolution of powers and a “soft” Brexit inside the European Economic Area (EEA) were the only way to protect Scotland from a Thatcherite “right-wing ideological experiment”, as ministers from London and Edinburgh gather for a fresh round of talks today.

Ms Sturgeon and Mrs May will hold their own face-to-face meeting next week, with the First Minister doubling down on her claim that Conservative plans for Brexit pose a risk to devolution.

Her comments in an article for The Scotsman today follow the unveiling of the EU’s negotiating guidelines for the next stage of Brexit talks, with Brussels warning that leaving on Mrs May’s terms will be “complicated and costly”. The UK Cabinet has settled on a policy of “ambitious managed divergence” from EU regulations after sustained pressure from pro-Brexit Conservative MPs, leading to claims from opposition parties that Mrs May’s government is seeking to erode standards in order to make the UK attractive to future trade partners.

First Minister Nicola Sturgeon and Mrs May will hold their own face-to-face meeting next week. Picture: Jane Barlow/PA Wire

Ms Sturgeon argues that “the benefits of devolution have been reinforced” by membership of the European single market, particularly the free movement of people, and says it is essential to “protect both our place in Europe and the powers of our parliament”.

“That’s why we, together with other parties and the Welsh government, are resisting Tory plans to take control of devolved powers as part of their Brexit package,” the First Minister says.

“It’s important to remember that the campaign for a Scottish Parliament was to a large extent a reaction against a right-wing Tory economic and social experiment, carried out against Scotland’s wishes and with devastating consequences for many communities.

“And when the devolution referendum came, it saw a resounding Yes-Yes vote. But today that overwhelming democratic endorsement is under threat from a Tory Westminster power grab.

“The danger for the next generation is that they will bear the brunt of another right-wing ideological experiment.”

Ms Sturgeon insists that the only way the Prime Minister can deliver on the agenda set out in a speech last week is to accept a Norway-style Brexit within the EEA – something the UK government has consistently ruled out.

“If the Prime Minister was able to unshackle herself from the hard-line Brexiteers currently dictating policy, she could aim for membership of the European Economic Area, meaning the UK could remain inside the single market, rather than having to negotiate its way back in – and then only partially so – through a complex series of arrangements,” Ms Sturgeon says.

“The services sector would be protected, the UK could still be influential in deciding standards regulations and the ‘level playing field’ on state aid, competition policy, environmental and labour standards would be achieved.

“In addition the UK would be outside the ‘direct jurisdiction’ of the European Court of Justice (the Prime Minister has now conceded an indirect role of the court) and the UK would be free to make trade deals with countries outside the EU – although the Scottish Government is clear in our view that the UK should also stay in the customs union.”

Setting out guidelines due to be adopted by the remaining 27 EU members later this month, European Council president Donald Tusk said “negative economic consequences” from leaving the single market were guaranteed.

“That is the essence of Brexit,” Mr Tusk added, despite the guidelines setting out the EU’s desire for “as close as possible a partnership” with the UK.

Mr Tusk said Brussels hoped for an “ambitious and advanced” free trade agreement (FTA) with zero tariffs on goods but limited access for services.

But he added: “This positive approach doesn’t change the simple fact that because of Brexit we will be drifting apart. Our agreement will not make trade between the UK and EU frictionless or smoother.

“It will make it more complicated and costly than today for all of us. This is the essence of Brexit.”

Mr Tusk said that under the terms set out by Mrs May, the only option available in negotiations was an FTA of the type signed with Canada.

And in a clear demonstration of Brussels’s reluctance to deliver the kind of bespoke deal outlined by the Prime Minister last week, he said: “I fully understand and of course I respect Theresa May’s political objective, to demonstrate at any price that Brexit could be a success and was the right choice. But sorry, it is not our objective.”

Ministers from the UK, Scotland and Wales will meet in London today, with hopes low that a breakthrough can be reached talks over claims of a devolution “power grab” in Brexit legislation.

The UK government is insisting on retaining an “emergency brake” covering around 25 areas of devolved responsibility returning from Brussels after Brexit, to avoid devolved administrations implementing different rules.

SNP Brexit minister Michael Russell says the Scottish Government must agree to devolved responsibilities being shared with London, rather than being consulted under UK government plans.

Nicola Sturgeon in soft Brexit appeal as Brussels warns PM over '˜costly' red lines