For many of us, the British Chancellor's annual budget announcement is a familiar ritual. We watch out for the extra couple of pence on a pint of beer or a glass of wine. We wince at the inevitable hike at the petrol pumps and wait hopefully for a few pounds back in tax credit or personal allowance.

But the UK budget doesn't just matter to 60 million Brits. Admittedly, not many of the world's poorest people will be gathered around the television watching George Osborne at the despatch box on Wednesday - but for some of them, his words are a matter of life and death. ONE decided to get to the bottom of the figures and find out just how important they are.

Our report, Small Change, Big Difference, reveals, for the first time, the true impact of UK aid around the world. This new audit of British aid spending plans shows that UK aid will put 15.9 million children in school, protect 5.8 million mothers during childbirth, provide safe drinking water to 17 million people and help over 9 million people overcome malnutrition in the next four years.

But all this will only be achieved if the Chancellor confirms in this week's budget that the UK government will reach its target of investing 0.7% of national income in international aid next year. This new research makes it clear: now would be the worst possible time for Britain to walk away from its promise to the world's poorest. Not just because lives and futures depend on it, but also because in tough times, smart aid is not just good for the poorest countries. It's good for Britain too. Aid helps countries grow, and as they grow they become potential markets and trading partners for UK plc.

This isn't about creating a never ending cycle of aid. The ONE report demonstrates how UK aid will help bring forward the day when aid is no longer needed. In the next four years UK aid will help 77.6 million people access formal financial services, such as bank accounts or credit - the basics needed to start a business. And it will help create employment opportunities for 19.3 million people by investing in infrastructure, supporting entrepreneurs, developing markets to sell goods, encouraging trade and investment, and increasing agricultural productivity.

During David Cameron's recent visit to the United States he and Barack Obama said that "As two of the world's wealthiest nations, we embrace our responsibility as leaders in the development that enables people to live in dignity, health and prosperity." Cameron is right to recognise our responsibilities as a wealthy nation - and he also knows Britain's aid promise is affordable. Even at 0.7% of national income, UK aid will account for just 1.6 pence in every pound of government spending.

In tough economic times, keeping our aid promise is more important than ever. No other budget achieves so much for so little. The government's bilateral and multilateral aid reviews demonstrated its commitment to fund the most cost-effective projects available and just last week the Department for International Development (DfID) linked up with the Serious Organised Crime Agency to ensure that any allegations of misuse of funds are properly investigated. Nobody claims aid is perfect, but British aid is good and getting better.

Each of these statistics on their own is remarkable but together they add up to one of the wisest and most far-sighted investments our government can make. No one wants aid to continue forever but if done properly this is an investment that will save and transform lives, boost economic prospects and help to bring forward the day when extreme poverty - and aid itself - is a thing of the past.

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