Scottish Secretary David Mundell has defended his department's spending on social media advertising to promote the UK Government's work in Scotland.

According to SNP MP Deidre Brock, funding for social media advertising at the Scotland Office was £13,000 in February and nearly £11,000 in March.

Ms Brock said the expenditure was far higher than that of the Welsh Office, which she claimed was around £71 for a summit in 2016.

Speaking at Westminster's Scottish Affairs Committee, Mr Mundell said it was important to demonstrate the role and work of the UK Government in Scotland.

He said: "I think it is important that we demonstrate firstly the respected powers and responsibility to Scotland, to Government and what we're doing.

"On social media we've promoted a number of things. We've promoted, for example, our Growth Deals.

"I think it's very positive for people to understand those deals - we've set out a range of activities that the Government has pursued."

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Mr Mundell said te Scottish Office in Edinburgh spends £700,000 a year on communications, compared to £2.6 million by the Scottish Government.

The Scottish secretary was also grilled on why the the findings of research commissioned by the Cabinet Office into public attitudes towards the Union have not been published.

The issue was raised by SNP MP Tommy Sheppard, who said his Freedom of Information (FOI) request to review the information was turned down.

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Mr Mundell said that analysis of the research was still ongoing.

He said: "I'm aware of certain aspects of it because that research, which all governments carry out and the Scottish Government carries out opinion research in relation to its policies.

"Research can be very detailed, certain parts of it are then analysed and used in conjunction with policy development."

Mr Sheppard said his latest FOI request had been refused on the grounds that it "related to the formation of Government policy".

He added: "Now that intrigues me because yourself, the Cabinet Secretary, other administrators have been clear to point out that they are not intent on reviewing the constitutional settlement or changing the policy on devolution, that what's going on is simply an administrative, organisational review within departments to see how they can work better and make the Union work better from your perspective.

"So I'm intrigued as to what policy then may be being reviewed that this research has a bearing on?"

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Mr Mundell told MPs he believes the review is in connection with all policy responsibilities in relation to the constitutional settlements, stating that the research was instigated some time ago.

He said: "There are very clear rules on which the Government operates and which are obviously observed by commissioners and independent bodies in relation to how they're operated in terms of how information is designated and which information is released or not."

Mr Sheppard concluded by confirming that he has lodged an appeal against the decision to reject his FOI request.