ITV Border's Political Editor Peter MacMahon talks politics and prebuttals

Peter MacMahon talks Scottish politics Photo: The Picture Editor

In the Malcolm Tucker-esque world of political operatives it's known as "prebuttal".

In other words it's not rebuttal, but the step before that.

Before your political opponents even say something, you say your piece and hope to set the agenda.

In rugby it would be called getting your retaliation on first.

Today the Scottish Secretary Alistair Carmichael has been indulging in a spot of light prebuttal ahead of the SNP's planned White Paper on independence, due to be published on 26 November.

In a speech in Inverness Mr Carmichael said the UK Government is highly unlikely to agree to a currency union with an independent Scotland.

First Minister Alex Salmond's assertion that "the pound is as much Scotland's as it is the rest of the UK's" is not backed up by international law, Mr Carmichael said in his first keynote speech since he replaced Borders MP Michael Moore in the UK cabinet.

And, in prebuttal style, he had a demand to make of the Scottish Government. In its White Paper it should, he said, set out "a credible plan B" on currency because their current plan "wouldn't work".

The SNP "seem obsessed with UK-wide solutions" in their independence plans, including shared currency, welfare, defence procurement and financial regulation, he added for good measure.

But these solutions are merely "a wish list" that could only be secured through negotiation with other states pursuing their own national interests, he warned.

We can expect much more of this kind of questioning of the SNP's plans ahead of the launch of the White Paper which is likely, I am told, to be a weighty tome.

Mr Carmichael and the UK government will say they are perfectly entitled to raise such questions. The position of the SNP in terms of their plans to retain Sterling has been the subject of intense debate.

Nationalist ministers say it would make sense for both Scotland and for the rest of the UK ( rUK) to keep Sterling if - when in their view - Scots vote Yes to independence.

It would be fair to say there are a wide range of views on whether this would be possible, with distinguished economists ranged on both sides.

The SNP has been challenged on the "what if" question on a number of occasions - what if the rest of the UK said it would not share Sterling?

So far Nationalists have avoided going down that road. They maintain that what remained of the UK after Scottish independence would, after negotiations, accept Scotland could continue to use Sterling.

It is hard to see SNP ministers deviating from this policy now, in the White Paper, or up to the referendum.

Though, as no-one can predict exactly what will happen were Scotland to become independent, it is surely a legitimate question for their opponents to ask.

There are, however, some nationalists who are prepared to think about alternatives. George Kerevan, for instance, a former SNP candidate, economist and journalist has written on this subject here:

http://www.newsnetscotland.com/index.php/scottish-economy/5230-currency-wars

Although written a little while ago, it still sets out an alternative to being in the Sterling zone, including Scotland having her own currency.

We can expect this debate to continue up to and after the publication of the White Paper which, we must hope, will shed further light on the crucial issue to Scots voters ahead of the referendum of the currency an independent Scotland would use.

So what might the fictional spin-doctor from In The Thick Of It have to say about all this? As far as we know Malcolm has not pronounced on the issue of the currency in an independent Scotland. Given his fruity style, it is probably just as well.

But watch out for more prebuttal, rebuttal, and possibly even pre-rebuttal to come.