House of Commons Speaker Sir Lindsay Hoyle was forced to step in to correct Boris Johnson during PMQs after the Prime Minister referred to the SNP as the 'Scottish Nationalist Party' instead of the 'Scottish National Party'

With the Prime Minister facing a grilling over his comments on devolution, Sir Lindsay Hoye told the Prime Minister to stop referring to the SNP as the Scottish nationalist party.

Sir Keir Starmer had opened up PMQs by asking Johnson to elaborate on comments he had made earlier in the week when he described devolution as “a disaster”. He said: “The single biggest threat to the United Kingdom is the Prime Minister every time he opens his mouth”

Responding to questions on the matter, the Prime Minister said: "What has unquestionably been a disaster is the way in which the Scottish Nationalist Party have taken and used devolution as a means not to improve the lives of their constituents, not to address their health concerns... but constantly to campaign for the break-up of our country" 

READ MORE: PMQs: Watch as Johnson grilled by Starmer and Blackford over devolution

Sir Lindsay Hoyle said: “Can I just say it’s the Scottish National Party, not the nationalist party.”

Mr Johnson replied: “Mr Speaker, I’m so sorry. They’re national but not nationalist. I see, right.”

Sir Lindsay replied: “We can play pedantics another time.”

SNP Westminster leader Ian Blackford hit out at the comments made by Johnson earlier this week saying: “His attack on devolution wasn’t just a slip of the tongue, it was a slip of the Tory mask.

“The chasm between Westminster and the Scottish people has never been bigger. We know that these were not just flippant remarks when Scotland faces the biggest threat to devolution with the Tory power grab Bill.

READ MORE: Boris Johnson branded a 'liability' after devolution disaster comments

“The fact is Scotland has been completely ignored by Westminster. We now face an extreme Brexit, a power grab and another round of Tory cuts all being imposed against our will by a Tory government that we didn’t vote for.

In a call with Conservative MPs on Monday, Boris Johnson reportedly said devolution was “a disaster north of the border” and “Tony Blair’s biggest mistake”.