Rachel Reeves has been urged not to cut the government’s environment funding in the budget as analysis shows the department’s finances were slashed at twice the rate of other departments in the austerity years.

Between 2009/10 and 2018/19, the environment department budget declined by 35% in monetary terms and 45% in real terms, according to Guardian analysis of annual reports from the Department for the Environment, Food and Rural Affairs (Defra), the Environment Agency and Natural England. By comparison, the average cut across government departments during the Conservative austerity programme was about 20%. During the first five years of austerity, it was the most cut department.

The budget for the department rose in the years between 2018/19 and 2021/22, but this is because it was given many new roles after Brexit, including taking on the £2.4bn a year farming budget which once came from the EU, and hiring staff to go through the EU statute book to see which environmental laws should be replicated in the UK. This new money, analysts argue, did not fill the gap left by deep cuts made under austerity, because it was ringfenced for new functions Defra did not previously perform.