For the pro-UK parties campaigning for a No vote in the independence referendum, it is a thoroughly distasteful prospect.

Talk about what would happen in the event of people voting Yes? That breaks a cardinal rule of politics, that one should never, ever concede the possibility of defeat. It is something that politicians simply do not do. In general elections, by-elections, at Question Time, on the radio and at hustings meetings, even politicians who are staring down the barrel at defeat will not discuss the hypothetical scenario of losing. For those who are doing well and are ahead in the polls, to do so would be considered laughably stupid.

Yet, like it or not, the UK Government parties are having to think the unthinkable about what would happen following a Yes vote and, worse for them, talk about it. In January, John McCormick, electoral commissioner for Scotland, called on the Scottish and UK Governments to agree a statement about what would happen following the referendum in September 2014. He had good reasons for doing so. He was responding to focus group evidence of confusion among voters over the process and timetable for negotiating Scotland's exit from the UK in the event of a Yes vote and what would happen following a No vote.

Since no action is required in the event of a No vote, that presents no difficulty; the sticking point is therefore over discussing what would happen if the outcome was Yes. It is not hard to see why Alex Salmond is more than happy to oblige. He will judge that the UK Government talking about the Yes scenario can only help make it seem more realistic and credible, but the pro-UK parties do not like it. The process has dragged on to such an extent that the two governments have missed the December 20 deadline set by Mr McCormick for their joint statement.

So what now? The fact is that voters need more clarity and information. The UK Government may not like it but it should agree with the Scottish Government the basic process that would take place following a Yes vote.

The UK Government faces a further headache. Yesterday, Alex Salmond said that the central difficulty with the talks as he saw it was that no government department in London was prepared even to have technical discussions over what would happen in the event of a Yes vote, but that is hardly surprising when to have department-by-department discussions would be to risk straying into pre-negotiation, something the UK Government refuses to engage in for understandable reasons.

All the Electoral Commission has asked for is a basic steer over what would happen following a Yes vote. It should be recognised that some things - such as how long the complex negotiations might take - are virtually impossible to answer, but voters still wonder how the country would be governed in the interim before Scotland had disengaged fully from the UK, and what the negotiations might cover. The UK Government cannot be expected to pre-negotiate, but voters deserve more clarity on the basics.