Nearly 5% of the population of Somalia died in the recent hunger crisis according to a report.
The Global Humanitarian Assistance (GHA) annual review of humanitarian financing, released by Development Initiatives, revealed that some 257,000 people, 4.6% of the population, died between 2010 and 2012 - and claims lives could have been saved with earlier intervention.
Judith Randal, executive director of Development Initiatives, said: "The data shows that the response to slow-onset crises such as Somalia is often late, resulting in huge numbers of unnecessary deaths. By intervening earlier, as well as investing in mechanisms that reduce risk, donors could save more lives and protect more livelihoods - probably at lower cost."
This year's report, released at the United Nations' ECOSOC meeting in Geneva, highlights the continuing vulnerability of the most disadvantaged people in developing countries, despite the fact there were no major natural disasters that led to large-scale loss of life in 2012.
It also exposes a funding gap, with 62.7% of UN humanitarian appeals met in 2012, the lowest proportion in a decade.
The report recommends donors provide funding to last several years, to spend more on disaster preparation and to intervene promptly.
Ms Randal said: "Humanitarian assistance is often seen as a short-term intervention with short planning cycles. But poverty will not be ended without improving underlying security and increasing resilience to crises."