Henry Northover, WaterAid's Head of Policy, said in response: "David Cameron is absolutely right to call on the world's richest countries to keep their promises to the poor. "Thanks to international aid and development over the last two decades, two billion more people now have access to life saving safe water. "By meeting our international commitment to spend 0.7% of our national income on aid, Britain can continue to lead from the front and champion getting water to the 783 million who are still waiting for it, and provide one of the most cost-effective interventions that brings the greatest returns in reducing needless child deaths. "Improvements in water and sanitation reduce illness and deaths and are vital to meeting many of the other development goals. Sanitation is one of the most off-track of the targets and diarrhoea remains one of the biggest killers of children in Africa." According to the Joint Monitoring Programme (JMP) that is coordinated by UNICEF and the World Health Organisation, 1.8 billion people have gained access to safe sanitation while two billion people have gained access to clean water from 1990 to 2010 (the latest figures available). Currently, 783 million people (around one in every 10) still lack access to clean drinking water, while 2.5 billion people (around four in every 10) lack access to safe sanitation. According to a 2012 briefing by WaterAid, Saving Lives, meeting the Millennium Development Goal target on sanitation – currently one of the most off track of the Millennium Development Goal (MDG) targets – would save at least 400,000 additional children's lives in 2015. Earlier this year, the JMP announced that the global MDG target on water had been met five years ahead of target in 2010. Significant regional variations remain, with many sub-Saharan countries unlikely to meet the 2015 target date to halve their populations without access to this essential service. The situation with sanitation is even further off track. Analysis by WaterAid demonstrates that at current rates, sub-Saharan Africa will not reach its MDG target on sanitation for another century and a half. Around 2,000 children under the age of five die every day due to diseases, such as diarrhoea, which in large part are brought about through a lack of clean water and safe sanitation.