IF Brexit has dominated the Conservative campaign south of the border then the prospect of a second referendum has occupied Ruth Davidson on a daily basis.

The Scottish Tories have put their opposition to another poll at the heart, often the only message, of their campaign.

Their stance however is not ‘never to a second referendum’ instead it is no referendum until “the Brexit process has played out” and “not unless there is public consent for it”.

The SNP say they want a referendum when the terms of the Brexit negotiations are known which Nicola Sturgeon now says should be “at the end of the Brexit process”. Exactly when this is is unclear.

Ms Sturgeon regularly says this election is not about independence but the manifesto is clear that a majority of SNP MPs in Scotland would strengthen the mandate for a referendum to be held.

A “triple lock” together with the 2016 Holyrood result and the vote in the Scottish Parliament.

Labour’s manifesto is arguably tougher on no second referendum than the Tories. It is opposed to a second referendum and puts no timetable on when one would be acceptable.

It states it is "unwanted and unnecessary” and the party says it will “campaign tirelessly to ensure Scotland remains part of the UK”.

Jeremy Corbyn however has said he wouldn’t block it if the Scottish Parliament and Scottish people wanted it.

It said the SNP “needs to respect the verdict of the majority of Scots in 2014 and abandon its divisive plan to re-run the referendum.”

The LibDems are also campaigning on a no referendum message.

The party leader Willie Rennie mentions it every day and the manifesto says: “We will work hard to ensure Scotland remains part of the United Kingdom. We will oppose a second referendum and oppose independence.”