The UK government has been accused of treating the Scotland Office as a marketing department to promote the Union as UK taxpayers have paid millions of pounds to cover the bill from the Scottish independence referendum.

In 2010, when the Conservatives came to power, the Scotland Office had two communications staff costing a little over £108k but in the last five years costs have increased fourfold rising to £474k for nine staff.

Revealed by the SNP through Freedom of Information, the figures have sparked a row with the UK government highlighting that for the same period the SNP's spending on 'public engagement' reached almost £5m.

"The Scotland Office now spends half a million of its tiny budget on just nine press officers - a staff cost of almost £6,500 per press release since April. It is clear that the Scotland Office's only role is a marketing campaign for the Union," remarked SNP MSP James Dornan.

Finance secretary John Swinney's draft budget shows £4.9m allocated for public information and engagement. This compares with more than £2m for communications staff salaries in 2010.

A spokesman for the Scotland Office told the press: "The UK government has a duty to inform the public about its policy and work. These modest year-on-year increases bring the office into line with similar UK departments. It also adds new functions such as digital communications, ensuring key information reaches as many people in Scotland as possible."