A criticial “window is closing” to prevent climate and debt crises impacting the long-term prospects of more than 800 million children around the world, the author of a major piece of research from charity World Vision has said.

The paper, which has been shared exclusively with The Independent, finds that 839m children across 55 countries could be hit by debt and climate pressures constraining investment in health, education, nutrition and protection.

Climate impacts and debt pressures are escalating across the developing world, the report finds, with the impact being felt particularly acutely by children, limiting health and education services that they rely on, and forcing them to miss out on crucial years of their childhood due to challenges including illness and malnutrition.

Every year of childhood is critical to development, the report argues, and governments including the UK must urgently prioritise support for climate resilience, develop a more effective programme of debt relief, and also focus more on children in foreign aid programmes.

“Climate change and debt are two converging crises threatening the long-term prospects of hundreds of millions of children around the world,” said Joanna Casson, policy manager at World Vision and lead author of the report.

“The effects of these crises are colliding in childhood, and with every year that passes, the window to prevent lasting damage to another generation of children grows narrower.”

Earlier this year, The Independent visited an aid area programme managed by World Vision in Tanzania, where interventions around nutrition, infrastructure, healthcare and sanitation were all being severely undermined by the escalating climate crisis.

The new report from World Vision comes after many months of intense lobbying from civil society, including in this newspaper, that wealthy creditors should do much more to support developing countries address spiralling debt costs, which have hit a 25-year high.

Countries including Laos, Malawi, Nigeria, Pakistan, Sierra Leone, Sri Lanka and Uganda are now spending more on interest payments than on health, education and social protection combined, World Vision finds. Together, these countries are home to 269 million children.

NGOs including World Vision are backing calls for UK legislation that would compel private lenders – who hold an increasingly large share of developing countries’ debt – to negotiate in good faith when a country seeks to restructure its debts.

The legislation would capitalise on the fact that 90 per cent of developing country debt eligible for G20 debt relief is legally domiciled in the UK – and would also allow countries to suspend debt repayments and also halt creditor lawsuits while negotiations are under way.

The government signalled a greater willingness to drive forward the debt relief conversation last week, when Ed Miliband called for a “new deal” on developing country debt at the World Bank Meetings in Bangkok.

“The short-term repayments are crippling, and while many are not defaulting on their payments they are being forced, if you like, to default on the lives and prospects of future generations,” he said.

The report from World Vision also recommends that much more foreign aid for climate support should come in the form of grants, rather than loans, so that money intended to help countries tackle the climate crisis does not exacerbate debt challenges.

A recent data-led investigation from The Independent showed how many of the poorest and most climate-vulnerable countries are being priced out of the climate aid system due to their inability to apply for loans, while countries able to access aid are seeing billions added to their already-critical levels of national debt.

This article has been produced as part of The Independent’s Rethinking Global Aid project