Truss won the Conservative leadership race after promising to enact a low-tax, high-growth agenda.

Following her mini-budget, the pound crashed and the Bank of England was forced to make an emergency intervention to calm market turmoil. She reveals she was given the “starkest of warnings” by senior officials that any further economic turbulence could leave the UK unable to fund its own debt.

Truss sacked Kwasi Kwarteng, her chancellor, and less than a week later, resigned as prime minister saying she no longer commanded the confidence of her MPs.

She writes: “I still believe that seeking to deliver the original policy prescription on which I had fought the leadership election was the right thing to do but the forces against it were too great.”

“I am not claiming to be blameless in what happened, but fundamentally I was not given a realistic chance to enact my policies by a very powerful economic establishment, coupled with a lack of political support,” she says.

She recalls entering office presuming her “mandate would be respected and accepted”.

“How wrong I was,” she writes.

She condemns “endemic” levels of “pessimism and scepticism” at the Treasury about the potential for growth in the British economy.

And in a damning indictment of the department, she reveals that in the run-up to the mini-budget, no one there highlighted any risks to pension funds – which would trigger unprecedented volatility in the gilt market – to either her or Kwarteng.

“At no point during any of the preparations for the mini-budget had any concerns about Liability-Driven Investments (LDIs) and the risk they posed to bond markets been mentioned at all to me, the Chancellor or any of our teams by officials at the Treasury,” she says.

This was a significant omission, she argues, because this issue “would ultimately bring my premiership to an abrupt and premature end because of the panic it induced”.

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“Only now can I appreciate what a delicate tinderbox we were dealing with in respect of the LDIs,” she adds.

Truss says her mini-budget was made a “scapegoat” for problems that had been “brewing” for a number of months including rising interest rates and mortgage costs, which had already been forecast to go up.

The former prime minister says it was not only domestic economic orthodoxy she was up against when she tried to challenge “high-spend, high-tax” policies, but that she was also “swimming against the international tide”.

“There was a concerted effort by international actors to challenge our Plan for Growth,” she says, citing remarks by Joe Biden, the US President, as well as comments by the International Monetary Fund (IMF).

Truss also criticises the failure within her own party to make the case for lower taxes and deregulation, which meant “the groundwork” was not in place for her radical economic agenda.

In an implicit swipe at the David Cameron, Theresa May and Boris Johnson administrations, she says successive Conservative governments since 2010 have instead “triangulated” with Labour policy.

“We have not done enough over the last decade to make the arguments for a lower-tax, more deregulated economy, which meant that the groundwork had not been laid for what I sought to do,” she writes.

She claims she was left “pushing water uphill” as large swathes of the public had “become unfamiliar with key arguments about tax and economic policy and over time sentiment had shifted Left-wards”.

Truss also says she was surprised at the reaction from fellow Tory MPs to her plans citing the “furore” over the announcement to scrap the 45 per cent rate of income tax.

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She defends her decision not to commission a forecast from OBR to go alongside the mini-Budget, saying it would not have been “appropriate”.

Truss acknowledges her communication “could have been better” but adds that the public service machine was not “enthusiastic” about promoting messages “contrary to its orthodoxy”.

And she argues that ultimately, improving public messaging would not have altered the course of events. “Although there are many ways in which the policy could have been better communicated or tweaked to make it more acceptable, I struggle to see how that would have changed the fundamentals of what happened,” she says.

Truss opens up about the toll her short-lived premiership took on her, saying “soul-searching has not been easy” and adding that it has been “bruising for me personally”. And she reveals her regret at sacking Kwarteng.

A senior government source said Truss’s approach “failed then, and will fail if tried again”.

The Telegraph, London

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