The analysis by the House of Commons Library, commissioned by the Liberal Democrats, revealed that three-quarters of a million more people, which includes 370,000 more Londoners and 280,000 more in the wider southeast, will be dragged into the 40% income tax bracket for the first time.

Nearly four in 10 of those set to pay the higher rate in the UK are in London and the southeast. It also found that around 280,000 more people in London and 350,000 in the southeast would be pulled into paying the 20% basic rate of income tax by 2025-26.