BORIS Johnson sacked David Mundell because he couldn’t be trusted, the outgoing Secretary of State for Scotland has claimed.

Alister Jack’s appointment to cabinet was one of the big shocks of the the new Prime Minister’s bloody reshuffle.

READ MORE: Alister Jack: who is the new Conservative Scottish Secretary?

Despite Ruth Davidson’s pleas to keep Mundell in place, Johnson decided a new man was needed.

Jack, unlike Mundell, has always been a Brexit supporter.

The SNP said the sacking was proof that Johnson didn’t rate Davidson.

Speaking on the BBC yesterday morning, Mundell said that Johnson told him he wanted to mould the new cabinet in his image.

“I think it is very important for Scotland that the secretary of state for Scotland does have the prime minister’s ear, his trust, his confidence and therefore I welcome this appointment,” he said.

Mundell said he believed the Prime Minister “didn’t feel I was maybe as on board with a no-deal Brexit as he would want me to be. I have always ... been clear that a no deal Brexit isn’t a good outcome”.

He added: “I don’t think no deal is a good outcome but on the other hand I am very, very clear that we have to leave the EU,” he said.

“We have to deliver on the electoral mandate from the referendum.

“If not I think that we face severe dislocation to our political system.”

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Mundell also defended his willingness to serve in Johnson’s cabinet despite previously being a vocal critic.

“I’m not going to apologise for being willing to compromise, being willing to work with people even though I have reservations about them.

“I have never been a cheerleader for Mr Johnson, I think people know that.

“Everything I have ever said about Mr Johnson is on record but yes I would have been willing to work with him to secure Scotland’s place in the Union and deliver Brexit.”

In one of his first interviews since taking the job, Jack told STV he would advise Johnson to refuse any request from Nicola Sturgeon to hold an independence referendum: “We settled that in 2014. It’s not back on the agenda,” he said.

The National: New Scottish Secretary Alister Jack backs BrexitNew Scottish Secretary Alister Jack backs Brexit

“It was a once-in-a-lifetime – once-in-a-generation, as the then-first minister said – referendum, and as far as I’m concerned the matter was settled then.”

The Scottish Secretary also denied that he got the job purely because he was a Brexiteer: “I was very fortunate to be picked, it was a great honour.

“But it wasn’t just because I voted Leave. There were many others who voted Leave. I think it’s because I brought some experience.”

Jack’s appointment has been met with a mixed response from the Scottish Tories.

One Holyrood frontbencher told The Times: “Alister is capable but the reason he is so popular with the UK party is because he invites ministers to his country estate. It is not the image we want to project.”

That comment infuriated some of Jack’s Westminster colleagues.

“Bollocks. He is popular because he is capable, competent, pragmatic and loyal,” West Aberdeenshire and Kincardine MP Andrew Bowie tweeted.

Millionaire Jack, a serial entrepreneur who made his fortune through tents and storage, was first elected in 2017 at the snap election. He was a whip for Theresa May before Johnson promoted him.

According to his register of interests, the 57-year-old’s many businesses include gyms in London and growing Christmas trees in Lockerbie.

He’s been involved in Tory politics for decades and some papers even tipped him as a future party leader.

Jack stood for Holyrood in 1999 but unexpectedly withdrew from that election saying he needed to concentrate on expanding his fledgling business.

Thanks, in part, to the size of his bank balance, the businessman been an influential figure in the party.

In 2011, he backed Murdo Fraser over Davidson in the Scottish Tory leadership contest.

Jack said Fraser would shake the party up and were he to win “significant sums of money will be in place”.

The SNP’s Tommy Sheppard said Jack was “a multimillionaire, landowning, Tory Brexiteer”.