Ministers have been urged to reverse a decision to freeze all “non-essential” international aid until autumn, with Labour demanding that the government clarify the criteria for blocking the programmes. The Treasury has blocked “non-essential” new payments for overseas aid projects over the course of the summer recess, purportedly because high spending on Ukraine and Afghan resettlement means the budget will breach the new 0.5% gross national income spending limit. The block, first reported by the Financial Times, was ordered by the chief secretary to the Treasury, Simon Clarke, who wrote to the Foreign Office and other Whitehall departments telling them to stop spending on non-essential projects. Downing Street denied that any “life critical” aid would be cut back, saying the freeze would mostly affect longer-term building and infrastructure projects. The shadow secretary for international development, Preet Gill, said she was outraged by the block on funding. “If this decision goes ahead life-saving assistance will be withdrawn from millions at the shortest of notice and people will die,” she said. “In the middle of a global food security crisis, it is simply unacceptable that Britain’s crucial support and the lives of the world’s most vulnerable people are being treated as collateral in your party’s Conservative leadership contest.” In a letter to the chancellor, Nadhim Zahawi, Gill said the Treasury was evading scrutiny by not bringing the decision to parliament. She asked Zahawi to urgently clarify “which of Britain’s life-saving aid programmes do you consider to be ‘non-essential’?”, and to set out criteria being used to block payments and the timeline for doing so. “Does the government intend to defer or delay aid payments, or cancel payments entirely?” she said. “As chancellor, you have committed not to make short-term decisions that would have lasting consequences ahead of your party selecting a new leader and prime minister. With this in mind, I urge you to reconsider and reverse this decision.” Boris Johnson’s spokesperson said the pause of “non-urgent” spending was because of the significant sums being spent in supporting Ukraine. “It allows us to ensure these programmes are properly funded within the current aid budget,” they said, adding that it would be up to departments to decide which projects to stop funding for. Britain’s overseas aid budget was cut by Rishi Sunak last year, citing the pressures of pandemic spending, from a commitment to spend 0.7% of national income on aid to 0.5%, but the change is intended to be temporary. The former international development secretary Andrew Mitchell criticised the move and said it would cost lives. “Clearly the government has to live within budgets agreed by parliament, but to withhold spending on life-saving projects in this way will undoubtedly cost lives and further impair the UK’s reputation,” Mitchell told the FT.