There should be no disputing that the Scottish National party government in Edinburgh has an electoral mandate to trigger a referendum on Scottish independence during the lifetime of the 2011-16 Holyrood parliament. The SNP's manifesto for the 2011 elections said they wanted such a referendum and in May the voters gave them a majority. The fact remains, however, that while the Scottish government may have a mandate for a referendum, it nevertheless lacks the authority to hold one. The authority to hold a constitutional referendum lies with the UK government in the Westminster parliament, not with the Scottish government at Holyrood. So a referendum called by the Scottish government would arguably be beyond its powers, could be challenged in the courts and might not have legal or even political authority either. That is not a situation that anyone, whether they are for or against independence, should seek.

It is therefore high time that the mandate and the authority were brought into alignment, so that Scottish voters can make their choice and settle the matter one way or the other. That means there must be some grown-up co-operation between Edinburgh and London to make sure both that there is a referendum and that it is fair and lawful. But this is where politics come in.

The SNP, not wishing to recognise the authority of the UK or its government, acts as though mandate and authority are one and the same (which they are not), while also being aware that winning any independence vote would be an uphill task (an Ipsos-Mori poll, reported yesterday, showed only 29% support for independence). The SNP is therefore keen to play for time. It stands for St Augustine as well as St Andrew. Give us an independence referendum, but not too soon, is its prayer.

On the other side, the Conservative-Liberal Democrat coalition, with little voter support in Scotland (the two parties lost 17 Holyrood seats between them last May), acknowledges the SNP's mandate but is anxious both to assert its own authority and to prevent the breakup of the UK. Yet it knows that any initiative it takes will be denounced by the SNP as unwarranted interference and may risk recruiting further support for the independence cause. Until now this has meant that the London government has been pinned into a corner by the SNP. But this stalemate could not go on indefinitely, however much that suits the nationalists.

It is wisest not to take yesterday's initial locking of horns at face value. But the UK government's attempt to break out of its corner is an important event all the same. It will confirm today that it is offering the Scottish parliament the authority to hold a referendum, but with conditions. Those conditions include putting only a straight yes or no choice on independence on the ballot paper (even though many in Scotland actually want the third option of more devolved powers), putting the non-partisan UK election commission in charge of the campaign, and holding the vote sooner rather than later. The move is a gamble and the initial Scottish government response was predictably contemptuous. The SNP will not agree without a loud fight, if at all. But this is a conversation which needed to move on. Now it has. And then it needs to finish.

In the end, the arguments over process are disputes which ought to be reconcilable. Fair supervision, a clear question for voters and a consistent electoral roll are not issues that ought to divide honest leaders. The difference between holding the vote in 2013, as London wants, or 2014, as the SNP now seems to prefer, is not unbridgeable either. The Scottish electorate must decide on the future of Scotland in a vote whose meaning and authority are beyond challenge. That is not easy when the referendum has become such a political plaything. Times are hard in Scotland as elsewhere, and the uncertainty over process and outcome, though sometimes exaggerated, should not be allowed to block all other issues facing the country. Get on with it, all of you.