Researchers estimate that Britain’s cuts alone could result in 5.1 million additional deaths by 2030, while France’s reductions could lead to 3.5 million and Germany’s to almost 2.9 million.

The findings come as European governments sharply increase defence spending in response to geopolitical tensions and wars, and after the Trump administration gutted USAid.

Last year, Britain announced aid cuts alongside plans to raise defence spending to 2.5% of GDP. This is now scheduled to rise to 3.5% by 2035 in line with Nato targets. Germany and France are also increasing military spending while reducing development budgets.

“Development cooperation has long functioned as a stabilising tool – strengthening health systems, reducing fragility and mitigating the drivers of conflict and displacement,” the report said. “Weakening it may ultimately prove more costly than sustaining it.”