Andy Burnham’s handling of the British economy is so “reckless” that he would be struck off for negligence if he were a medical doctor, according to one of his former aides.

Former Bank of England chief economist Andy Haldane claims the prime minister’s failure to reduce the UK’s borrowing costs in the Budget could result in the nation suffering an economic “heart attack”.

Writing in , he compared Mr Burnham’s approach to “not renewing your home insurance at the same time your next-door neighbour’s house is ablaze”.

In a devastating attack, Mr Haldane, who informally advised Mr Burnham on economic policy after taking office in July, said Britain’s finances were “on a knife-edge with most of the lights on the fiscal dashboard flashing red”.

He criticised the way Mr Burnham “rails against crude cuts”, arguing his policies could have precisely that effect by risking a repeat of Liz Truss’s catastrophic 2022 Budget, and “swamp the poor” in the process.

Mr Haldane also dismissed Mr Burnham’s proposed sweeping economic reforms, hailed as “progressive” by his supporters, saying they were “neither prudent nor progressive”.

Mr Haldane, who is president of the British Chambers of Commerce and turned down the offer by Mr Burnham of a formal No 10 role, says it would be a “mistake to take comfort” from recent reports suggesting the UK had “weathered the worst of (recent) financial storms”.

In fact, the UK’s current fiscal position was “more precarious today than at any time in the past half-century”, he says in his article.

The UK’s borrowing costs were higher than any other nation in the G7 group of major industrialised democracies despite having a lower debt burden.

Mr Haldane suggested the reason for this was that Mr Burnham and chancellor John Healey’s plans, which include reducing the UK’s “fiscal headroom” from £23bn to £16bn, “lack credibility in the eyes of financial markets”.

To meet its fiscal challenges, the government needed to raise £30bn to £40bn by tax rises or spending cuts - but had avoided this in its “do no harm Budget,” said Mr Haldane.

He writes: “Facing this fragility, what was the government’s Budgetary response? To run down its fiscal reserves rather than bolstering them. This is equivalent to not renewing your home insurance at the same time your next-door neighbour’s house is ablaze.

“Running down our insurance cover is an act of reckless complacency.

“The UK’s financial blood pressure is sky-high. In this situation, a doctor would prescribe clinical intervention to reduce the risk of a financial heart attack, including statins and slimming routines.

Instead, Burnham’s government had “offered homoeopathic remedies” including “higher deficits and debts, taxes and spending”, Mr Haldane said.

He added: “A doctor prescribing this course of treatment would probably be struck off”.

Mr Haldane warned the country faced the danger of the kind of economic collapse seen in Greece in 2009 and after the Truss Budget – which at worst could “swamp the poorest”.

He said: “While the government rails against using ‘crude cuts’ to restore fiscal order, cuts come no cruder or crueller than following a financial crisis. Ask Greece.

“By failing to take our insurance, the government is putting at risk those very people it claims to represent. This is neither prudent nor progressive”.