Institute for Fiscal Studies says chancellor may have to revisit tax plans to avoid real-terms cuts in some areas

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Rachel Reeves could need £9bn of further tax increases to avoid a fresh round of austerity for some struggling public services, despite her first budget setting out the largest rise in a generation, the Institute for Fiscal Studies has said.

After the chancellor delivered Labour’s first budget in 14 years on Wednesday, the leading experts in public finances said she could be forced to top up her tax plans to avoid real-terms cuts in some areas, including councils, the justice system and prisons.