FORMER First Minister Alex Salmond has called on the Treasury’s top civil servant to resign after a report by a group of influential MPs criticised the mandarin’s behaviour in the run-up to the referendum.

The Public Administration Select Committee’s report into civil service impartiality, released today, has criticised Sir Nicholas Macpherson, the Treasury’s Permanent Secretary, for publishing a letter to Chancellor George Osborne advising against a currency union between an independent Scotland and the rest of the UK.

According to the report, Macpherson’s decision to publish the letter “compromised the perceived impartiality of one of the UK’s most senior civil servants”.

At the time, Macpherson defended his decision saying it was to “reassure the markets”, a defence the committee rejected.

Salmond said: “This report will be devastating for the Treasury. The committee brush aside Sir Nicholas’ excuse that he was attempting to ‘reassure markets’. Sir Nicholas’ position is untenable – he is totally distrusted by the Scottish Government and is unrepentant.

“He should do the honourable thing and resign.”

The Treasury declined to comment on Salmond’s resignation demand.

A spokesperson said: “As we have made clear before, the question of whether or not the UK would agree to a currency union was an exceptional case where it was important that the arguments were exposed in full before a referendum rather than after it.”

The spokesperson also referred to a speech by Macpherson in January where he said that he had published the advice “because I regarded it as my duty”.

He said: “The British state’s position was being impugned. Demonstrating that the political and official state were completely aligned would further strengthen the credibility of the Government’s position. And it was important that the arguments were exposed before the referendum rather than after it.”

One of the committee’s conclusions was that the Government should guarantee “the publication of advice to ministers will never recur”.

“The decision to publish,” the committee warns, “will have unintended consequences for advice given to ministers on future major issues – including referendums.”

As reported in The National and the Sunday Herald last week, Macpherson has come under pressure over the impartiality of the treasury. Emails last week suggested the Treasury was working with Better Together.

Civil servants working at the Treasury were sending information that undermined the case for independence to newspapers.

The Public Administration Select Committee’s report also criticised Scottish Government civil servants over their role in the production of a white paper on independence.

The document, the committee argued, contained details of what the SNP would introduce if it won the 2016 Scottish Parliament election.

“The committee concludes that the Scotland’s Future White Paper did not uphold the factual standards expected of a UK Government white paper. Parts of it should not have been included in a Government publication and this raised questions about the use of public money for partisan purposes. Civil servants should not carry out ministers’ wishes if they are being asked to use public funds to promote the agenda of a political party.”

A spokesperson for the Scottish Government, however, defended the paper: “The Scottish Government is clear that the white paper, Scotland’s Future, met the highest professional standards, that its contents were entirely appropriate for a Government publication and was a proper use of public funds.”

Pointing to last week’s Budget, the Scottish Government argued that UK and Scottish administrations of all political persuasions regularly “set out policy intentions whose implementation depends on the outcomes of future elections”.

The spokesperson added: “It is the role of the civil service to work with the elected government of the day to implement its policies. It is not in any dispute that the Scottish Government elected in 2011 stood on a platform of supporting independence and of holding a referendum.

“There was broad agreement that the Scottish Government should set out its proposition for independence to inform voters ahead of the referendum.”

The Public Administration Select Committee started its inquiry into civil service impartiality last June. It was announced just days after Macpherson’s letter was published.

The committee, made up of Conservative, Labour and Liberal Democrat MPs, took evidence from civil servants, journalists, and ministers.