A TORY MSP has written a letter to the Scottish Government’s top civil servant demanding answers over Humza Yousaf’s appointment of a minister for independence.

Donald Cameron, the Scottish Conservatives’ constitution spokesperson, said he believed the Government was acting outside its powers and responsibilities by appointing MSP Jamie Hepburn to the role.

He has written to the Scottish Government’s permanent secretary John-Paul Marks to ask whether he had approved the appointment.

Cameron asked whether the permanent secretary had objected to the decision to appoint a minister for independence and whether his objections, if made, were overruled by the First Minister.

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He also demanded to know Yousaf’s “justification” for spending “public money on an area” outside the powers of the Scottish Government, arguing that constitutional matters were reserved to Westminster.

Cameron wrote: “Did you object to Mr Yousaf’s decision to appoint a minister for independence? And, if so, did the First Minister issue a formal ministerial direction to instruct you to facilitate that spending?

“Given the appointment has now proceeded, it is my understanding that such a direction may already have occurred.

“If it has, can I further request that you provide the justification given by Mr Yousaf for spending public money on a area which is not within the competency of the Scottish Government?”

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In a statement, Cameron said: “It’s a scandalous and flagrant attempt by Humza Yousaf to divert public money to promote the party-political goals of the SNP on a matter outside the Scottish government’s competence.”

He added: “The Supreme Court ruling last November was clear and unequivocal that the Scottish government has no authority to unilaterally hold an independence referendum – so there is no function for this minister other than cheerleading for the SNP.”

A Scottish Government spokesperson said: "The First Minister has appointed a ministerial team that reflects the priorities that he will pursue in government – including tackling child poverty, improving public services, building a fairer, greener economy, and giving people the information about devolution and independence that they need to make an informed choice about Scotland's constitutional future.

“The Permanent Secretary has received the letter from Mr Cameron and will respond in due course.”