While three parties campaigned against independence in 2014, Scottish Conservative leader Jackson Carlaw insists his is the only one that can now be relied upon to stand up to Nicola Sturgeon.

As they did under previous leader Ruth Davidson, the Tories have focused their campaign strategy around a defence of the Union.

Mr Carlaw is unashamed about this, saying: “Our message is stop indyref2, it is take on Nicola Sturgeon and make her focus on the appalling record of failure in Scotland’s public services.”

And with voters apparently believing Jeremy Corbyn would grant the SNP leader the second vote on independence that she craves, Mr Carlaw says his party are now winning over traditional Labour voters in the party’s former west of Scotland heartlands.

The Scottish Conservative campaign has been focused on halting demands for a second independence vote (Andrew Milligan/PA)

He insisted that the Conservative vote is “holding firm” after the party won 13 seats in 2017 – a result that then helped keep Theresa May in Downing Street.

And despite Boris Johnson’s unpopularity – a recent poll have him a net approval rating in Scotland of -52 – Mr Carlaw says the Tories are getting a “fantastic response in certain key seats”.

He spoke of a “sense that the Conservative vote is holding firmly in Scotland”.

Mr Carlaw added: “There are other people, particularly old Labour unionists who are dismayed by what Corbyn is doing and saying who are thinking ‘I want to stop Nicola Sturgeon, how do I do it’.

“If you want to stop Nicola Sturgeon, I think in this election, the Conservatives who are now Scotland’s opposition party, are the party to do it.

“I’m getting feedback that we are having a fantastic response in certain key seats, particularly in the west of Scotland, where that old Labour unionist vote exists, those people are dismayed by what Jeremy Corbyn is doing.”

While the Tories united with Labour and the Liberal Democrats to fight to keep Scotland in the UK in the run up to the 2014 referendum, Mr Carlaw said five years on from that vote, “people have increasingly come to see that actually only one of those unionist parties can be relied upon to be firm and resolute in standing up for the Union”.

He added: “They believe Jeremy Corbyn is quite prepared to do a deal with Nicola Sturgeon on a second independence referendum if that gets him into Downing Street.

“They look at the Liberal Democrats….. but they have been quite confused in their messaging as the campaign has gone on, and their ratings have slumped.

“I think increasingly people are saying if I want to stop Nicola Sturgeon which party is going to do it, and there is only one, that’s the Scottish Conservatives, the party I am leading.”