Nationalists who seek to divide Scots depending on their voting intentions in next year's independence referendum are on "dangerous territory", according to the Scottish Secretary.

Alistair Carmichael will warn against "mixing up politics and patriotism" in his first constitutional speech since his appointment last month.

He will say he is a "proud Scot", drawing on his upbringing on Islay, work in Glasgow and Aberdeen and current life in Orkney to argue that support for independence does not make a person a "better Scot".

Speaking in Inverness on Wednesday, Mr Carmichael will say: "Not content with trying to divide the UK, the supporters of independence also seek to divide our fellow Scots - depending on their voting intentions in the referendum.

"I tell you this - once you start mixing up politics and patriotism you can quickly get into dangerous territory."

Deputy First Minister Nicola Sturgeon said: "I agree that no one's Scottishness should be questioned on the basis of their political views - or indeed on the basis of whether or not they drink malt whisky!

"My own family background is part-English, with a grandmother from England, but like so very many people of mixed heritage who live and work here in Scotland, I passionately believe Scotland's future should be in Scotland's own hands.

"As it happens, unlike Alistair Carmichael, I don't drink malt whisky - but I am looking forward to toasting a historic Yes vote next year and the huge opportunities that will bring to people, families and communities all over Scotland."

He will contrast "positive and unifying" support for the UK with the negativity and "wrecking ball" politics of the nationalist camp.

Mr Carmichael will say: "We share our resources and we pool our risks. Where it makes sense to act as a United Kingdom on issues like cyber crime, banking and pensions that is exactly what we do. We are stronger and safer together as a result.

"When it makes sense to have decisions taken in Scotland by the Scottish Parliament we devolve the responsibility to Holyrood. It is the best of both worlds. It is a constructive and positive approach. Our instinct is to be constructive and find what works best.

"Those who lead the case for independence do not share that instinct. They prefer a wrecking ball politics that would dismantle the UK. It is hard to think of anything more negative than to constantly campaign for breaking up a 300 year partnership.

"Their answer to every problem is to leave the UK. The option of working together and sharing is always less attractive to them than going it alone and building barriers. We must confront this negative approach head on.

"The referendum is an opportunity to put divisions behind us. I want people to support the positive reasons Scotland should remain in the UK."

Deputy First Minister Nicola Sturgeon said: "I agree that no one's Scottishness should be questioned on the basis of their political views - or indeed on the basis of whether or not they drink malt whisky!

"My own family background is part-English, with a grandmother from England, but like so very many people of mixed heritage who live and work here in Scotland, I passionately believe Scotland's future should be in Scotland's own hands.

"As it happens, unlike Alistair Carmichael, I don't drink malt whisky - but I am looking forward to toasting a historic Yes vote next year and the huge opportunities that will bring to people, families and communities all over Scotland."