Liz Truss has warned she must cut the mini-budget to save her premiership

He said Mrs Truss should now consider what “amendments she may need to make to get the Finance Bill through the House of Commons”.

“The Finance Bill will pass the mini-budget and the Finance Bill will be an opportunity for her critics to attack, knowing that if they kill two Finance Bills then she will probably be forced to resign.

“That would be the scenario where the men in gray would have to figure out what the alternative was.”

Ben Wallace or Rishi Sunak among the alternatives

An alternative could be Ben Wallace, the defense secretary, or Rishi Sunak, the former chancellor.

He added: “Depending on what happens in Ukraine, we could be in a pretty dangerous situation in November, when actually the party has to rise above itself and decide what’s best for the future of the country, not different from the future of the party and find out what a compromise candidate might look like.

“Whether it’s Ben Wallace, as a warlord-type decision, or whether it’s really economic stability that the party needs to establish; is it Rishi, who certainly had command of the markets when he was chancellor, although he was not an instinctive tax-cutter.”

Mr Lewington said the Bank of England should move its rate-setting meeting from November 3 to the same time as the Office for Budget Responsibility’s medium-term forecast on October 31.

He said: “In the 1990s chancellors set both fiscal policy rates at the same time and now the chancellor does not have the flexibility.

“Obviously, because there is an imbalance, if I can put it nicely, between what the Bank of England is trying to do and what the Chancellor is trying to do, there is an argument to be made to persuade the Bank of England to move its meeting to setting interest rates possibly until the morning or even the day before.

“[That would ensure] that the Tariff Committee is aware of all the measures to be announced the following day.”

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