ROME - Efforts to save starving Somalis and others suffering from drought in East Africa were ratcheted up Monday, with UN agencies pitching for $1.6 billion from donor countries and private companies being urged to provide trucks, ships and other logistical aid to speed food to the malnourished.

Rome-based UN Food and Agriculture Organization chief Jacques Diouf told an emergency meeting on the Horn of Africa crisis that a pledging conference would be held in Nairobi, Kenya, on Wednesday to seek $1.6 billion in aid over the next 12 months, with $300 million of that aid coming in the next three months.

Monday's emergency session was held at the request of France, which is making development of agriculture in poorer countries a priority in international policies.

The speed of the stepped-up efforts appeared to take some by surprise. The US ambassador to the UN food agencies, Ertharin Cousin, told reporters she didn't immediately know if her country would be boosting its contribution on top of what it has already given.

US Secretary of State Hillary Rodham Clinton announced last week that the US will provide an additional $28 million in aid for Somalis suffering from hunger, on top of more than $431 million in emergency assistance to the eastern Horn of Africa this year.

The United Nations' top humanitarian and relief official, Valerie Amos, told reporters that so far just under $1 billion has been received from donors so far, but that "we need another billion."

Germany said Monday it is donating an additional euro15 million ($22 million) in humanitarian aid for the worsening famine. That doubles the amount pledged earlier this year by Berlin for the drought problem.

More than 11 million people are estimated to need help in East Africa's worst drought in 60 years, in Kenya, Ethiopia, Somalia, Eritrea and South Sudan. But Somalia is the "epicenter of the famine," said UN World Food Program executive director Josette Sheeran.

Some mothers have had to make the "horrifying choice of saving the strongest" of their children while leaving the weakest behind to die as starving families make the long, desperate trek from Somalia to refugee camps across borders in search of food aid, said Sheeran.

Compounding the drought are soaring food prices.

In Somalia's case, two decades of fighting by warlords have complicated its security. Currently, Islamist militants in the al-Qaida-linked Al-Shabab militia are attempting to overthrow a weak UN-backed government, worsening security for UN and other aid organizations.

Al-Shabab signaled earlier this month that it would accept aid groups it had previously banned, but changed course last week, saying groups like WFP are not welcome. The militia denies there's a famine, disputing the UN's assessment that tens of thousands of people have already died.

The World Bank's promise Monday of more than $500 million to help the drought victims noted that while the money would be spent on projects in Ethiopia, Kenya and Djibouti, in Somalia, the funds would only be used "where circumstances permit." That was a reference to al-Shabab.

The UN World Food Program has said it cannot reach 2.2 million Somalis at risk of starvation.

"We're trying to help the people where they are," said Amos. She was referring to the growing numbers of desperate Somalis who, exhausted and carrying children near death, reach relief camps in Kenya and Ethiopia.

Also trying to do their part are private sector companies. A former CEO of TNT, Peter Bakker, told The Associated Press that he will working the phones later Monday calling top executives of food production and transport companies to see what may be able to contribute to help the UN speed food to starving people in the Horn of Africa.

UN officials say that in some parts of Somalia more than half the population suffers acute malnutrition.

Amos was asked about what she called "extremely serious" allegations in media reports that some UN officials were asking payments to let refugees receive food at the camps. "We will be investigating these allegations," she told reporters.

At least one UN official at the Rome meeting said Africa must do more to feed its own people. The Horn of Africa famine is "an indictment of our leaders," said Kanayo F. Nwanze, a Nigerian who heads the International Fund for Agricultural Development, a UN agency trying to help small-scale farming in poor countries.