He supported the previous prime minister however was the fourth Cabinet member to give up in July final yr.

Some 62 resignations ended his time in Downing Street.

In an interview with the Institute for Government, Mr Lewis known as Mr Johnson’s ousting “hugely unfair” after his “massive mandate from the country”.

But he mentioned that “it was untenable at that point. I was in No 10 for two or three hours the night before, and I actually said to him, ‘When you can’t field a government, as unfair as it is, it’s over.

"And he couldn’t really field ­a government. I also felt my position was untenable because he had offered me two promotions. If it hadn’t been so late at night and [Buckingham] Palace had gone to bed, he would have announced one of them because he kind of just said, ‘You’re doing it.’

"And I was a bit like, ‘I’m not sure about this.’ I just thought, ‘I can’t do that, and I’ve effectively now been moved from Northern Ireland to do this other thing, so my position’s untenable anyway.’ It was just farcical. So I just felt I had no choice. But I found it really difficult.”

Mr Lewis returned to Cabinet as Justice Secretary beneath Liz Truss, who served as prime minister for 44 days.

Sir Robert Buckland, Wales secretary in her administration, recalled the “deeply upsetting” expertise of the Truss authorities. He advised the IfG that her time “started with high hopes” and “seemed to be well ordered”.

But the “watershed moment” got here after the mini-Budget final September which included the most important tax cuts since 1972, funded by an unlimited growth in borrowing.

Sir Robert mentioned there had not been the “fullest appropriate disclosure” to Cabinet members about what they have been going to do. He added: “It might have led to a more informed discussion at Cabinet about the wisdom of rushing ahead with all those announcements at once, which, of course, we all know really sowed the seeds of the ­unravelling of the proposals.

“And I am very, very sad about it because a lot of what we were trying to do wasn’t wrong.

“In fact, a lot of it was right. And she’s been elected by the membership of the Conservative Party, so she deserved support. But they were the authors of their own misfortunes. It was deeply, deeply upsetting to be involved in that.”