The deaths of up to 100,000 people in the drought-affected Horn of Africa could have been minimised had there been a swifter reaction from the international community and aid agencies, according to a report.

The study by Oxfam and Save the Children says early warning systems forecast an emergency situation as early as August 2010, but a full-scale response to the drought did not start until July last year.

It said donors wanted "proof of a human catastrophe before acting to prevent one".

By that time, malnutrition levels had deteriorated and parts of Somalia had already been declared famine zones.

Al Jazeera's Barbara Angopa reports.