Britain's finances remain 'vulnerable' despite Labour's £68billion of tax hikes, according to a damning Budget assessment by S&P.

The ratings agency warned that Chancellor Rachel Reeves' plan to balance the books could unravel before the next election and said her Budget did little to boost growth.

Labour's tax rises since taking power now total £68billion, doubling fiscal headroom to £22billion – the amount left after meeting borrowing targets by 2029. 

But S&P said the UK faces average deficits of 5.5 per cent of GDP between 2022 and 2024, with NHS and welfare spending outpacing revenues. 

The plan relies on freezes to income tax thresholds and raids on property, dividends and salary sacrifice schemes from 2028, just before the election in 2029 – raising fears of a U-turn.

S&P added: 'We consider the UK's fiscal position as vulnerable.'

Rival Moody's said the plans also assume a freeze on departmental spending, which may be 'difficult to implement in an election year'.