THE UK Government has been urged to spend tens of millions of pounds on promoting Unionism amid fears Scotland could soon be independent.

At a meeting of Theresa May’s Cabinet, Tory ministers were warned they would need to implement a permanent “campaign mode” to convince Scots not to support a Yes vote, according to The Herald.

At an hour-long meeting of top UK Government ministers – dubbed the “Union Cabinet” – May insisted that the “Union had never been more important”.

The Cabinet was told a “permanent campaign focus” was required to maintain and strengthen the Union, which would necessitate tens of millions of pounds in spending, The Herald reported.

That will mean an increase on the share of UK Government spending on promoting the Union – which stands at just £100,000 out of a £440 million budget marketing.

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One minister is also said to have raised fears that Labour leader Jeremy Corbyn would accept proposals for indyref2 in exchange for SNP backing at Westminster.

The prospect of Boris Johnson becoming prime minister is also reported to be causing alarm about a possible spike in support for independence, especially if the UK leaves the EU without a deal on October 31 as Johnson has pledged to do.

Both he and leadership rival Jeremy Hunt have said they will block a second independence referendum if they become prime minister.

READ MORE: Tory leadership race: Hunt puts Johnson under pressure over Brexit pledges

It was pointed out to ministers the SNP administration spends £24 million annually on international relations even though this is a reserved matter for Westminster.

A Whitehall source told The Herald: “There was a general acceptance at Cabinet we have to move into campaign mode in terms of how we take forward our commitment to strengthen the Union.

“There was a recognition we must continue to make the case for the Union and it must be properly resourced.”

He added: “The Scottish Government is entirely focused on promoting the case for independence and the feeling is the UK Government has to think in the same way to promote the Union in terms of policy, spending money and communications.”

Last week during a visit to Scotland, May said the UK must work more "cleverly, creatively and coherently" to maintain it, agreeing with former prime minister Gordon Brown that it was under serious threat.

Her de facto deputy, David Lidington gave an even more stark warning, saying: “The Union is under more pressure than I've known previously in my lifetime.”

The SNP's Pete Wishart commented on reports of a huge Tory cash boost to combat indyref2 on Twitter.

"The Scottish Affairs Committee will have the Secretary of State for Scotland in front of it today. I’m pretty sure we will want to ask him about this," he tweeted.