The Scottish Government will formally ask MSPs next month to withhold consent to Boris Johnson’s controversial post-Brexit Internal Market Bill.
In a new legislative consent memorandum (LCM), the Scottish Government states the legislation “undermines both the devolution settlement and agreed ways of working across the UK”.
The UK Bill initially sparked outcry after ministers admitted it would break international law.
It would allow the government to renege on key parts of the divorce deal the PM struck with Brussels last year in relation to Northern Ireland.
But separately, the Scottish and Welsh governments have blasted the Bill as an “abomination” and an “assault” on devolution which steals powers from the devolved parliaments.
UK ministers say the legislation is necessary to protect jobs and that Scotland will be getting more than 100 new powers back from Brussels.
Nicola Sturgeon’s government disputes that claim, saying the Bill would effectively allow Downing Street to overrule it on issues like food and environmental standards – even in devolved policy areas.
Its LCM argues the Westminster legislation “explicitly gives UK ministers wide new powers in currently devolved areas of economic support and allows for breaches of international law”.
The Internal Market Bill already passed its first parliamentary hurdle in the House of Commons and is currently at committee stage.
Under the Sewel Convention, the House of Commons is not expected to legislate in devolved areas without the express consent of the Scottish Parliament.
In practice it does not legally prevent the UK parliament passing such legislation against Holyrood’s wishes, and it has done so on a number of occasions during the Brexit process.
However, Scottish constitution secretary Michael Russell said it would be “outrageous” for Johnson’s government to ignore an LCM opposing the Internal Market Bill.
He said: “UK Government ministers have accepted the Bill will break international law.
“It would be equally outrageous if they decided also to break the constitutional convention that the Westminster parliament does not legislate in devolved areas without the consent of the Scottish Parliament.
“The UK’s established constitutional rules mean that the consent of the Scottish Parliament is required for the UK Government’s Internal Market Bill to proceed.
“If the parliament refuses to grant consent then that should kill the Bill stone dead.
“It will demonstrate beyond all doubt that the UK Government does not believe the UK to be a partnership of equals.”
Russell claimed the legislation “opens the door to a post-Brexit race to the bottom and will mean democratic decisions of the Scottish Parliament on public health, environmental standards, food standards and a range of other key areas can be over-ridden”.
He said the Scottish Government “could never recommend the parliament agrees that its powers should be eroded so fundamentally”.
The UK Government says the Bill is necessary to replace the EU common market as Britain exits the Brexit transition period at the end of the year.
For EU member states, the common market governs things such as food and environmental standards and energy efficiency regulations.
This would be replaced by a new UK-wide internal market system.
But the UK Government has acknowledged this would mean Scotland having to accept goods and services from the rest of the UK even if they don’t meet standards enshrined in Holyrood legislation.