FRUSTRATED UK ministers are poised to intensify their Brexit Bill row with Edinburgh by setting out publicly in detail which powers it wants to hold back from Holyrood so that common countrywide frameworks can be agreed.

Last year, David Mundell, the Scottish Secretary, revealed to The Herald that he wanted to publish the list of powers coming back from Brussels, including those Whitehall wanted covered by common frameworks to protect the UK’s internal market.

But he said he had not done so at the request of the Scottish Government; a claim forcefully denied at the time by Michael Russell, the Scottish Government’s Brexit Minister.

Now, as the political heat over the Bill intensifies, a leaked Cabinet Office paper, sent to Theresa May and other ministers, suggests the UK Government is preparing to publish the list - with or without the consent of Nicola Sturgeon and her colleagues - in a bid to refute the First Minister’s claim of a Westminster “power-grab”.

Mrs May and her colleagues have become increasingly frustrated at the charge, which they fear has been gaining credence across the public. Not only Edinburgh but also Cardiff insists the EU Withdrawal Bill as it stands represents a bid by Whitehall to undermine the devolved settlement by holding back powers that should go directly from Brussels to the Scottish Parliament and Welsh Assembly.

The leaked paper says: “We will seek to publish this document with the devolved administrations’ support but I am seeking agreement to publish even if this support is not forthcoming.”

It explains that while the analysis on frameworks is provisional it does set out on which specific areas common cross-border policy is needed. It is thought these areas include agriculture, fisheries and environmental protection.

The document goes on: “Importantly, this demonstrates the limited number of policy areas in which legislative arrangements are thought to be necessary.”

It then adds: “It will allow us to rebut the ‘Westminster power-grab’ narrative deployed by the Scottish and Welsh Governments, which has been difficult to counter in the abstract. It will also allow us to demonstrate greater transparency in the frameworks process.”

The document was leaked to the BBC just hours before David Lidington, the Cabinet Office Minister, was due to sit down once again for talks with Mr Russell to break the deadlock over the bill.

Responding to the leaked document, the Scottish Government Brexit Minister tweeted: “Text of leaked letter makes it clear that UK MInisters were discussing it last week and will push on no matter what Wales & Scotland says. So much for a ‘partnership of equals.’”

No 10 insisted it did not comment on leaked letters but the PM’s spokesman said: “I would absolutely refute the narrative of a power-grab. Our track record on devolution is proven and our focus is finding a way forward that respects and strengthens the devolution settlement.

“We have always been clear we expect a significant increase in power for the devolved administrations as a result of this.”

Asked if the Withdrawal Bill would not go ahead without the consent of Holyrood, the spokesman replied: “We are clear this is a vital piece of legislation for delivering a smooth Brexit for all parts of the UK and what we are focused on is reaching an agreement with the devolved administrations.”

Later in the Commons chamber, the SNP’s Pete Wishart urged the Government to make a statement on the constitutional row, arguing the reason why ministers were finding it difficult to counter the power-grab argument was “because that is exactly what it is”.