IAN Blackford has declared there is “no case for the Union” as he insisted a referendum will take place next year.

The SNP Westminster leader invited deputy prime minister Dominic Raab – standing in for Boris Johnson at PMQs as he attends a Nato summit in Madrid – to present his argument for Scotland to stay in the Union.

It comes after Nicola Sturgeon unveiled her route map to a second independence referendum, which she intends to hold on October 19, 2023, pending the result of a Supreme Court battle with the UK Government.

If that bid is rejected, she says the Scottish Government will consider the next General Election a “de facto” independence referendum. A majority of votes for pro-Yes parties would be considered a mandate to begin negotiations to leave the Union, according to Holyrood ministers.

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Insisting the referendum will go ahead next year, Blackford told the Commons: “Scotland has already paid the price for not being independent. Westminster governments we did not vote for imposing policies we don't support. Breaking international law, dragging Scotland through the damaging Brexit we didn't vote for and delivering deep austerity cuts.

“Contrast that with our European neighbours, who have greater income equality, lower poverty rates and higher productivity. Why not Scotland?

“In the weeks and months ahead, we will make the positive case for independence. Will the opposition, if they can, make the case for continued Westminster rule?”

Raab, seemingly taking a swipe at Blackford, began by saying “it’s always good to see him in his place”. It came after calls for the SNP Westminster to chief to resign over the Patrick Grady row.

He told the SNP MP: “It's not the right time for another referendum, given the challenges that we face as one UK “I think actually the people of Scotland want their two governments to work together and we are keen, willing and enthusiastic to do so.”

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In response, Blackford announced: “There is no case for the Union, as we’ve just heard from the deputy prime minister.”

“The harsh reality is that the Tories might fear democratic debate, but they don’t have the right to block Scottish democracy.

He pointed out that Scottish Tory leader Douglas Ross had told voters ahead of the 2021 Holyrood election that a vote for the SNP is a vote for indyref2.

“You won’t often hear me say this,” Blackford told MPs, “but I agree with him and so do the Scottish people.

“Scottish democracy will not be prisoner of any prime minister in this place.”

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“So why is the UK Government scared of democracy? Or is it simply because they have run out of ideas to defend the failing Westminster system?”

Raab again refused to give credence to the notion of a second referendum.

“I think he’s rather airbrushing history with that long soliloquy,” the Justice Secretary said.

He insisted Scotland is facing a “huge tax burden imposed by the SNP” and concerns over educational standards.

“I think the people of Scotland expect their government in Holyrood and in Westminster to work together to tackle the issues facing them in their day-to-day lives.”