Whitehall departments have been told to make the defence of the Union a top priority across communications, policy and spending as UK ministers were warned the UK Government faced an “urgent political challenge” in Scotland.

Yesterday, The Herald reported how Cabinet ministers were urged to adopt a permanent “campaign mode” to save and strengthen the Union and to be as pro-active in this as the SNP Government was in promoting Scottish independence.

Indeed, in a briefing paper to Cabinet colleagues, marked “official-sensitive,” David Lidington, Theresa May’s de facto deputy, suggested the SNP administration was using one tourist marketing campaign as a cover to promote independence.

He wrote: “The Scottish Government have a multi-million pound marketing campaign, Scotland is Now. While the campaign is ostensibly aimed at attracting tourists, investment and migrant workers, in reality it is aimed at domestic audiences, promoting the idea of Scottish distinctiveness and implicitly independence.”

The paper said, noting how Brexit had increased pressure on an already sensitive political situation, that the “underlying trends on identity and demography” coupled with the retraction of the UK Government from key areas of Scottish life because of devolution were “posing real risks to the integrity of the UK”.

Mr Lidington told colleagues: “In Scotland, we face a significant, urgent political challenge,” given the nation’s majority vote for Remain and demands for more powers over immigration.

He pointed out how pressure on the constitutional position “remains high” and would increase if Nicola Sturgeon was able to guide the SNP to a majority in the 2021 Holyrood elections. Noting how the First Minister had already introduced a bill to set the framework for future referendums and how there were calls for a second independence poll before the end of next year, the minister noted how these “sharply highlight the ongoing risks to the Union”.

The Cabinet Office Minister suggested:

*departments develop “ambitious, nation-specific plans that demonstrate the Government is delivering in all parts of the UK, mobilising UK leverage to deliver outcomes in Scotland, Wales and Northern Ireland”;

*a “more rigorous approach to branding UK Government funding” as a means of strengthening recognition of its role and activity in Scotland;

*demonstrating how well London and Edinburgh can work together, countering criticisms the Scottish Government was being "ignored" and

*departments should in their bids during the upcoming Spending Review “articulate how their proposals contribute to the Union objective”.

Mr Lidington also warned of the “critical risk to the longevity of the Union” if the strategic dangers facing Northern Ireland, including the possibility of a post-Brexit border poll, were not effectively tackled.

Together with a perception in Wales that its interests were being ignored by London and an increased vote share for Plaid Cymru as well as a “growing ‘England-centricness’ and indifference to the Union, the minister said this meant Government efforts across the devolved nations had to be “mobilised”.

As the political uncertainty across the UK sees no sign of diminishing with Brexit unresolved and a new Prime Minister about to take office, Mr Lidington set out two key principles.

Firstly, that the issue of the Union had to be “considered early” and as a “fundamental part in all policy-making” across all Government departments.

He explained: “Departments should be required to set the pace in a more proactive way by owning, developing, steering and delivering projects that strengthen the Union and to show expert understanding of the impact in the different nations of any and all of the projects they have under development.”

Secondly, that the UK Government demonstrated it “respects and supports devolution”, that devolved government was the “optimum and permanent constitutional settlement for citizens, particularly when in opposition to a Scottish government that has a strategic interest in arguing that devolution is incapable of delivering and so should be replaced by independence”.

Under a so-called “Union strategy,” the minister said well-resourced communication campaigns were key to emphasising the “value of the Union”.

He warned against complacency given that the majority of day-to-day services were now delivered by Edinburgh but noted: “A strengthened communications approach, tailored for each nation, will seek to demonstrate the security and prosperity benefits of the UK, counterbalancing messages from devolved administrations.”