Boris Johnson has launched a tirade against the idea of Scottish independence in a heated exchange with Ian Blackford. 

Hitting out at the Prime Minister at PMQs, Ian Blackford said the Prime Minister was willing to “throw Scotland under his big red bus” to deliver Brexit.

He added: “This Prime Minister’s extreme Brexit will take a wrecking ball to the economy and cost Scotland and the United Kingdom up to £70 billion a year.

“You know, we can talk about the impact of Brexit and they’ll howl and complain because they know the reality. It is going to damage people’s lives. Isn’t the truth the Prime Minister is willing to throw Scotland under his big red bus to deliver his Brexit? No matter what the cost?”

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Hitting back at the idea, however, Boris Johnson said that the greatest damage that can be done to the Scottish economy would come from the SNP’s plan for independence

Mr Johnson replied: “The greatest damage that could be done to the Scottish economy would be their reckless plan to break up the union with the UK.

“Sixty per cent of Scotland’s exports are with the rest of the UK. They would be throwing away not just the biggest block grant in history that Scotland has received this year but of course all the benefits of membership of the most successful political partnership in history.”

HeraldScotland: Speaker John Bercow during Prime Minister's Questions in the House of Commons, London.Speaker John Bercow during Prime Minister's Questions in the House of Commons, London.

"From shipbuilding in Govan to the Glasgow climate change summit next year, which will be a glory for our whole the United Kingdom, which is coming to Scotland precisely because Scotland is part of the United Kingdom. 

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"And they would throw that all away with their crackpot plan for borders at Berwick and creating a new Scottish currency or joining the Euro, or worse still going into the European Union, handing back control of Scotland's fisheries, Scotland's spectacular marine wealth just, at the moment they've been won back by this country, handing back control of those fisheries to Brussels. That's their policy, I look forward to contesting it at the barricades." 

Hitting back, the SNP leader said that PMQs was not the time for a “rant” from the PM adding that he will welcome Johnson to Scotland as every time he comes up, he drives up support for the SNP. 

Blackford added: "Scotland didn't vote for Brexit and we won't have it forced upon us.

"Isn't it clear the SNP is the only party standing up for Scotland's interests and respecting our democratic decision to stay in the European Union?"