SNP MSP Joan McAlpine has accused the UK Government of ditching the Barnett Formula to “short change” Scotland of £1.8 billion.

Last week Michael Gove announced a £650 million package for Northern Ireland as he pledged an “absolute commitment” to the people ahead of Brexit.

That sum is set to provide trade support technology, customs help and peace and reconciliation work.

But it has not been processed through the Barnett Formula that’s been in place since the late 1970s to determine spending levels for UK nations.

And the SNP says that if it had been, Scotland would be liable for a payment of more than £1.8bn.

The National: Joan McAlpine was gobsmacked to receive the missive from the Department for Exiting the EU at lunchtime yesterday

Now Joan McAlpine MSP (above) has launched a furious challenge to the Cabinet Office, accusing ministers of leaving Scotland to face a “double whammy blow of a bad Brexit deal” and “power grab” internal market proposals without the support it needs.

She said: “Any attempt to short change Scotland is not acceptable.

“Funding across the UK is supposed to be determined by the

Barnett formula – the Tories can’t dish out large chunks of cash to Northern Ireland while snubbing Scotland.

“With less than five months to go until Scotland is dragged out of the EU with the UK, it’s clear that any deal is going to hammer Scotland’s economy. Now, by ripping off Scotland to the tune of £1.8bn, the Tories are choosing to throw thousands of jobs and livelihoods on the scrap heap.

“The fact that they are providing additional funds for Northern Ireland is a tacit acceptance that the costs of Brexit are going to be high – but Northern Irish businesses aren’t the only ones going to be hit.

“Scotland’s businesses will be affected too, not least those who send goods back and forth to Northern Ireland. We will also feel the pain and burden of Brexit, compounded by the attack on devolution at the core of the Tories’ internal market proposals.”

The £1.8bn claim is based on population figures. Headcount is a key factor in determining spending through Barnett Formula and, when taken as a proportion of the English figure, Scotland’s total is 2.88 times higher than that of Northern Ireland.

READ MORE: Michael Russell says Scotland will fight against Tory power grab

Multiplying £650m by that sum gives an outcome of £1.87bn.

McAlpine said: “Boris Johnson’s Government think they can treat Scotland however they like and get away with it. With independence we will always be able to manage our own finances, grow our economy and protect Scottish jobs. It’s no wonder that prospect is looking more desirable every day.”

The £650m funding comes on top of the £1bn issued to Northern Ireland by Theresa May in exchange for support for her minority government from Arlene Foster’s DUP. That party had ten MPs at the time and the “confidence and supply” deal ensured May could stay in power.

Announcing the new funding last week, Gove said it “underlines our absolute commitment to the people and businesses of Northern Ireland”.

The move came around five months before Brexit comes into force on December 31.

No deal has yet been struck and concerns over the impact of the change on trade and other factors remain.

If the UK leaves without an agreement, the Westminster Government has said it will expand customs facilities in Northern Ireland, with new electronic import declaration rules set to come into play.

However, ministers insist that no separate customs infrastructure will be built and Northern Irish firms will have unrestricted access to the rest of the UK market.

Meanwhile, a Westminster white paper on creating a “UK internal market” post-Brexit has come under fire from devolved administrations over its plan to give Westminster control of subsidies like state aid. Devolved powers over food safety, animal welfare and minimum pricing could also be affected.

Michael Russell has branded it a “naked power grab” said it is evidence that the UK Government is “seeking to centralise power and promote free market dogma over the competence of the devolved parliaments”.

Speaking in the Holyrood, Russell said: “What the UK Government wants is not smooth trade but to take back control. And not just from the EU but from the people of Scotland and Wales and Northern Ireland.

“And it certainly does not want anything to stand in its way as it wilfully dismantles the high quality system of regulation and protection we inherit from our years in the EU.

“The Scottish Government is committed to co-operation but it will not be bullied. I can assure Scotland that this Government will fight the proposals tooth and nail, in every possible place.”

Scottish Conservative Murdo Fraser argued the UK internal market is “vital” for the economy.