Borrowing has overshot forecasts by £3bn in July, in a setback to Rachel Reeves ahead of her maiden Budget.
The UK borrowed £3.1bn in July, much higher than the £0.1bn predicted by the Office for Budget Responsibility and the highest borrowing for that month in three years.
The worse-than-expected figures come as the Chancellor is plotting to raise taxes and cut spending in October to plug a £22bn black hole in the public finances.
In the first four months of the financial year, the UK borrowed £4.7bn more than forecast at £51.4bn.
The figure is slightly lower after the Office for National Statistics revised down borrowing by £1.5bn, in a small relief for the Treasury.
Ms Reeves has committed to have debt falling as a share of gross domestic product in the fifth year of her forecast.
Darren Jones, chief secretary to the Treasury, said: “Today’s figures are yet more proof of the dire inheritance left to us by the previous government. A £22bn black hole in the public finances this year, a decade of economic stagnation, and public debt at its highest level since the 1960s, with taxpayers’ money being wasted on debt interest payments rather than on our public services.
“We are taking the tough decisions that are needed to fix the foundations of our economy, modernise our public services and rebuild Britain so we can put more money back into people’s pockets across the country.”
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