G8 leaders have been accused of neglecting a pledge to fight hunger in poor countries.
Anti-poverty group ONE said the drought crisis in east Africa is a "wake-up call" to Governments who pledged to help feed the hungry in Africa two years ago.
A spokeswoman from the group said leaders of the rich world meeting at the G8 summit in Italy in 2009 pledged 22 billion US dollars (£13.7 billion) to go towards agricultural projects designed to put Africa on the road towards food self-sufficiency, rather than on emergency aid during famines and disasters.
But a report published on Sunday found that since world leaders pledged the cash, only a fifth of the money has been donated. With just one year to go until the deadline for the donations, the report found that the UK has only pledged 30% of the 1.7 billion dollars (£1.1 billion) it pledged, a ONE spokeswoman said. She said that collectively the countries have raised 22% of the financial pledges.
ONE executive director Jamie Drummond said: "World leaders are guilty of letting slide their promises to fight the root causes of hunger, in particular very low agricultural productivity in regions like sub-Saharan Africa. We should not need a food crisis to wake us up to the need to not just give food aid now, but also deliver on the promised partnership with African leaders, citizens and the private sector to boost yields across the region.
"Fortunately with food security on the agenda of the G20 later this year there is a real opportunity for a new partnership to turn this around. With the right support, Africans can both feed themselves and export to the world, helping them fight hunger and poverty and helping us all with lower food prices."
A ONE spokeswoman said the Government deserves praise for pledging emergency food relief for 1.3 million people in Ethiopia for three months in response to the current crisis. The Department for International Development donated £38 million to the World Food Programme which will provide the food aid that the Disasters Emergency Committee (DEC) will be distributing.
The worst drought in over half a century has hit parts of East Africa, affecting more than 10 million people. Thousands of families have travelled for days across scorched scrubland from Somalia to Kenya, including barefoot children with no food or water, after their crops and livestock were destroyed by drought.
The DEC, the umbrella body representing the UK's 14 leading aid agencies, said acute malnutrition has reached 37% in some parts of north east Kenya and child refugees from Somalia are dying of causes related to malnutrition either during the journey or very shortly after arrival at aid camps.
British donations to a DEC appeal for support have now risen to £8 million, the committee said. But the situation is set to deteriorate over the next three to four months and campaigners say continued funding is vital.