THE UK Defence Minister has been dubbed “unfit for office” after he compared listening to an Ian Blackford speech to being waterboarded.

Johnny Mercer doubled down on the comments after facing a backlash, insisting he would rather be subject to the form of torture than listen to the SNP Westminster leader.

His comments came after Blackford was heckled by Tory MPs yesterday during a point of order in the Commons.

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Conservative members shouted “hooray” as Blackford indicated he would be concluding his speech.

The SNP MP said: "Well there you have it – there's the message to the people of Scotland, sit down and shut up.”

Tory James Cleverly is said to have shouted: "Not all of them. Just you."

Reacting to the incident on Twitter, Mercer wrote: “Cleverly is right. Blackford is the equivalent of parliamentary water boarding.”

Scotland’s Brexit Secretary Michael Russell was among those to condemn the comment.

He wrote: “This man is, apparently, a Defence Minister in the UK Government. His tweet demonstrates that he is utterly unfit for office but also reveals – no doubt unwittingly – the truth about what the Tories hypocritically call the ‘precious union’.”

But Mercer was not finished.

Facing a wave of criticism, he insisted he “liked” Blackford before stating his preference for waterboarding over listening to a speech by the SNP MP.

“Calm down,” he tweeted, “I like Ian a lot. But his speeches really are something else. It’s funny – he knows what he is doing, but I can assure you it is torture to listen to.

“For the avoidance of doubt I do not condone waterboarding. But I would volunteer for it over one of his speeches.”

The Tory minister has again been met with a wave of criticism online.