African countries and donors pledged more than $350 million Thursday at a fund-raiser in the Ethiopian capital to help millions facing starvation in the Horn of Africa's worst drought in decades.

The African Development Bank offered $300 million to fund long-term projects, while African states and other private donors pledged $51 million, the African Union Commission chief Jean Ping announced.

Ping initially said some $356 million had been promised, but later told reporters that the final figure was $351.7 million.

"This is the first time Africa is showing solidarity for an African cause," the bloc's chairman and Equatorial Guinea's President Teodoro Obiang Nguema said.

Two years of failed rains has left 12.4 million people across the Horn of Africa in danger of starvation with war-torn Somalia the worst affected country in the region.

Last month, the United Nations, for the first time this century, declared a state of famine in five Somali regions and said it could spread to engulf the country's entire south.

The drought has also left millions in parts of Ethiopia, Djibouti, Kenya and Uganda facing starvation.

The fund-raising conference was the first of its kind by the pan-African body, which has so far pledged only $500,000 of the needed $2.4 billion (1.6 billion euros).

However, only four heads state, -- Obiang, Ethiopian Prime Minister Meles Zenawi, Djiboutian President Ismael Omar Guelleh and Somali leader Sharif Sheikh Ahmed -- attended the Addis Ababa meeting.

Asked whether he was disappointed by the low turnout by African leaders, Ping said: "The first thing that is important is the figure ... So look at the amount and you will agree with me."

"We are very happy as a starting point," he added, noting that they had expected around $10 million in pledges.

A pan-African fundraising campaign, Africans Act 4 Africa, had criticised African governments and the AU for not responding quickly enough to a crisis that worsened two months ago.

"What we expected at the conference is that a lot more governments would be here, that a lot more governments would contribute and we havent seen that," said Irungu Houghton, a director at aid group Oxfam.

A Ghanaian schoolboy however heard the appeal and contributed $4000 -- double what the African nation of Lesotho pledged.

Eleven-year-old Andrew Andasi had launched a fundraising campaign after seeing television images of those struggling in famine-struck Somalia.

"I am feeling happy because I touched the hearts of the young and old, rich and poor," Andasi told AFP, thanking companies and friends in Ghana who donated to his cause.

Relief groups are struggling to expand aid deliveries, especially in Somalia where almost half its estimated 10 million people are in need of humanitarian assistance.

The Al-Qaeda-inspired Shebab rebels who control much of southern and central Somalia have restricted aid operations in their regions and have been blamed for worsening the drought.

Hundreds of thousands of Somalis have also fled to seek help in neighbouring Ethiopia and Kenya, but survival there remains a struggle due to congestion, threats of disease and insecurity in camps.

UN Humanitarian Coordinator for Somalia Mark Bowden warned Wednesday that Somalia's Middle and Lower Juba regions could be hit by famine, adding to the five regions already declared to be in famine.

European Union foreign affairs chief Catherine Ashton also Wednesday urged world governments to meet a "moral obligation" and increase emergency aid to the drought-hit Horn of Africa.

"The situation is grave, and it is a moral obligation of the international community to offer its help," she said.

Ashton said the EU's immediate humanitarian commitment for this year had risen from 97 million euros to 158 million, while national aid pledges from its member states totalled a further 440 million.

The UN's Food and Agricultural Organisation called Thursday for lasting solutions for Horn of Africa's recurrent droughts and lamented that funding for long-term agricultural projects was inadequate.

"We have the know-how, including frameworks, institutions, technology and human capacities to eradicate famine from the Horn of Africa, but we lack predictable resource flows to achieve that outcome," it said in a statement.