THE Scottish Government is demanding an apology after it was reported Nicola Sturgeon has drastically reduced the occasions on which the Union flag can be flown from public buildings.

The First Minister yesterday branded the claims “nonsense”, insisting civil servants had simply updated published guidance to reflect “long standing practice”.

Now the Government has written to three newspapers – the Daily Mail, Daily Express and Telegraph – giving 28 days for an apology to be issued.

READ MORE: Why we should flag up the dangers of the Saltire vs Union Jack row

It has threatened to take the case to the Independent Press Standards Organisation (IPSO), the industry regulator, if the issue is not resolved. It is understood part of the complaint centres on reports Ms Sturgeon was behind the decision.

The move marks the first time the Government has resorted to such a measure since the so-called “Frenchgate” scandal in 2015, when a discredited civil servant memo claimed Ms Sturgeon had told the French Ambassador she wanted David Cameron to remain in Downing Street.

It comes after a furious row erupted yesterday when it emerged published guidance had been changed to indicate the Union flag should only be flown on Remembrance Day, with critics accusing the SNP of "pushing its separatist agenda by stealth".

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Last year's guidance, which was also followed by related agencies such as Historic Environment Scotland, stated the Union flag should be flown on several occasions including Royal birthdays and anniversaries.

The Scottish Government said the guidance has been updated by officials to reflect actual practice, with former First Minister Alex Salmond revealing he changed the policy in 2010 after a conversation with the Queen at Balmoral.

He said: "It seemed obvious to me that the appropriate flag to be flown on the occasion of royal birthdays is the Royal Standard or The Lion Rampant.

"The only people who can order that to be done are the Queen herself and the First Minister as her representative.

"I remember the occasion very well. Her Majesty asked me if The Lion Rampant was a popular flag in Scotland. I was able to assure her that it was and indeed much beloved of Scottish football and rugby fans."

He said he brought the new policy into effect the following year which left the Union flag flying on Remembrance Sunday and Armed Forces Day, and branded press reports Ms Sturgeon made the change "complete piffle".

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Meanwhile, Ms Sturgeon took to social media to issue an extraordinary seven-part statement denying she had ordered any change.

She wrote on Twitter: “Since the truth doesn’t seem to matter very much to some, let me set out the facts on this ridiculous flag story.

“There are two essential elements to the story. One, that the Scottish Government has recently changed its practice on what flags to fly from government buildings on Royal occasions; and two, that I ordered such a change. Both are wrong.

“Since 2010, the Lion Rampant has been flown on Royal occasions – entirely appropriately. Since the Lion Rampant is the Royal Banner, it is not clear to me why anyone would object to that. However, the key point is that there has been no change to this since 2010.

“Yes, the civil service recently decided to update the published guidance, but simply to ensure that it accurately reflected the long standing practice – the underlying policy has not changed. And why would it?

“As for the claim that I ordered a change, I have issued no instructions, orders, authorisations – or even expressed an opinion – about changing flag policy. The update of the guidance was an administrative step – albeit a sensible one – and not done at my request.

“Sadly, the truth will not matter to some in today’s media – and that’s part of a much bigger problem, I’m afraid. But I still believe (hope) it matters to most in the media – and certainly to the public.

“Now I’ll leave those who are motivated to do so to argue about flags. I’ll get back to matters health, education, the economy and protecting Scotland’s interests.”

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Scottish Conservative MSP Murdo Fraser said: "The First Minister's Trump-style Twitter denial by candlelight last night does nothing to change the facts.

"The SNP issued a dictat on January 10 ordering Union Flags to be flown on one day and one day only.

He added: "She always stresses her civic nationalism is nothing to do with flags and banners. The events of the last 24 hours prove otherwise."

A Scottish Government spokeswoman said: “There has been no recent change whatsoever to the policy or practice relating to the flags that are flown from government buildings.

“The Royal Banner (Lion Rampant) has been flown on Royal occasions since 2010.

“The policy has not been changed under the current First Minister – the public guidance has simply been updated by officials in response to queries to match longstanding practice.”