TWO leading Conservative MSPs have said Holyrood should reject the UK government’s main Brexit legislation as it would fundamentally undermine the devolution settlement.

Tory constitution spokesman Adam Tomkins and finance spokesman Murdo Fraser signed up to a unanimous cross-party report savaging the EU (Withdrawal) Bill.

Backbench Tory Alexander Burnett also agreed with the criticism.

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The Bill, as currently drafted, would see all powers repatriated from the EU at Brexit go to Westminster, including more than 100 in devolved areas such as agriculture and fishing.

UK ministers would then be in sole charge of deciding which, if any, would be devolved and when.

Some powers would be never be passed on, but would be subject to UK-wide “common framework” agreements designed to protect the UK’s internal market.

The SNP say this runs counter to a basic tenet of the devolution settlement - that powers not specifically reserved to Westminster go to Holyrood by default.

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The Scottish and Welsh governments have described it as a “power grab” and called for devolved powers to be repatriated directly to the devolved legislatures.

Under the Sewel convention, Holyrood is asked to give its consent to Westminster legislating on its behalf in areas touching on devolved legislative and ministerial powers.

However the Scottish Government told parliament in September it would not lodge a legislative consent motion (LCM) because of problems with the Bill as drafted.

In an interim report published today, Holyrood’s finance and constitution committee essentially agrees with the SNP government’s complaints and says it cannot recommend Holyrood giving legislative consent to the Bill in its present form.

The 11 MSPs - five SNP, three Tory, two Labour and one Green - heavily criticised Clause 11 of the Bill, which deals with the repatriation of powers.

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They said it represented a “fundamental shift in the structure of devolution in Scotland”.

The UK government says the clause is a temporary measure before Holyrood enjoys a “powers bonanza”.

But the MSPs said that, regardless of extra powers for Holyrood, the clause would “adversely impact upon the intelligibility and integrity of the devolution settlement”.

Even as a transitional measure, it “fails to fully respect the devolution settlement”, they said, noting there was no explicit guarantee in the Bill it would be temporary.

“The committee will therefore not be in a position to recommend legislative consent for the Bill unless Clause 11 is replaced or removed,” they said.

The committee noted Scottish Secretary David Mundell has promised Clause 11 would be amended, but this has not happened yet.

The MSPs added they were “deeply concerned” the Bill would give UK ministers the power to create secondary legislation in devolved areas without the consent of either the Scottish Parliament or Scottish ministers, saying “this cuts across the devolution settlement”.

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Bruce Crawford, the committee’s SNP convener, said: “The committee is unanimous in its view that it is not in a position to recommend legislative consent to the EU Withdrawal Bill.

“The whole committee is of the view that Clause 11, as currently drafted, is incompatible with the devolution settlement in Scotland.

“This view was shared by the vast majority of expert evidence we received on Clause 11 as it represents a fundamental shift in the structure of devolution in Scotland.

“The Committee also believes that a resolution to Clause 11 is required regardless of whether a way forward on Common Frameworks can be arrived at.”

However he also said the committee welcomed a vow from the UK government that common frameworks would be agreed with Holyrood, not imposed.

Mr Tomkins, the deputy convener and a law professor at Glasgow University, said: “All of the committee welcomes the progress that has been made between the UK Government and the devolved governments in developing an approach to agreeing common UK frameworks and notes that this work is on-going. In particular, members welcome the UK Government’s commitment to respect the devolution settlement.”

SNP Brexit minister Mike Russell said: "We have been clear that all returning powers that relate to devolved areas must stay devolved after Brexit. Unless the UK Government makes significant changes, then in order to protect the Scottish Parliament, we will have no choice but to pursue the option of our own legislation - a Continuity Bill for Scotland."

A UK Government source said the report was not a surprise and ministers remained confident of amending Clause 11 in a way that would satisfy the Scottish Government.

Scottish Labour leader Richard Leonard said the SNP were using Brexit "to divert attention away from their record in government and towards their obsession with the constitution".