David Mundell urges Nicola Sturgeon to share a platform with him for campaign against British exit from EU

But the Conservative Cabinet minister said his offer to share a platform with senior SNP politicians would emerge if the package of reforms go ahead – and if he backs keeping Scotland and the UK within the EU.

Angus Robertson, the SNP’s Westminster leader, had pressed Mr Mundell to personally campaign for Britain and Scotland to remain.

He also insisted making a positive case is “crucial” as he warned Mr Mundell not to repeat the “grinding negativity” of the “project fear” tactics used by those who opposed Scottish independence at the 2014 referendum.

Speaking during Scotland questions, Mr Robertson told Mr Mundell: “The single European market and the ability to impact the legislation that governs it is hugely important to the Scottish economy – especially the exporting sectors, such as Scottish whisky.

“Will you confirm that regardless of the ongoing negotiations, you will personally campaign for Scotland and the UK to remain within the European Union?”

Mr Mundell replied: “You will know, and I’m sure will be pleased to have heard, that the leader of the Scottish Conservative and Unionist Party, Ruth Davidson, has expressed exactly that position.”

Mr Robertson pressed Mr Mundell a second time on the issue, adding: “Making a positive case for remaining in the EU will be crucial in the weeks and months ahead.

“So will you give a commitment not to repeat the grinding negativity of ‘project fear’ and condemn ridiculous scare stories, such as those from the Prime Minister on immigration and the refugee camp in Calais?”

Mr Mundell replied: “I’ll make my position known when the negotiations have been concluded.

“But I make this offer to you – if the reform package goes ahead and if I am campaigning to keep Scotland in the European Union, I’d be delighted to join you, (Alex Salmond, SNP MP for Gordon) and the First Minister on a platform to make that case.”