NAIROBI: South Sudan’s top UN aid official on Saturday hailed a new peace deal and called for food aid to flow to counter the risk of mass hunger. A military spokesman said a cease-fire would take hold, but wary skepticism remained: This is the conflict’s second peace deal.

The truce signed by President Salva Kiir and former Vice President Riek Machar late Friday in neighboring Ethiopia calls for a cessation of hostilities within 24 hours and unhindered humanitarian access.

Though it is the second peace deal of the nearly five-month conflict, the two leaders did not attend talks that forged the first cease-fire in January. This time they stood face to face, a hopeful sign one week after US Secretary of State John Kerry met with Kiir in South Sudan’s capital and spoke to Machar by phone. Days later UN Secretary-General Ban Ki-moon flew in, adding to the pressure.

The warfare has thrown an extremely poor country up against the edges of severe hunger. A new analysis released Saturday by the World Food Program, Save the Children and South Sudan government found food needs deepening to “alarming” levels in areas isolated by conflict, particularly several counties in Unity state, where up to 75 percent of people face severe hunger.

The fighting, which has often pitted Kiir’s ethnic Dinka against Machar’s ethnic Nuer, has killed thousands of people, often in what a new UN report this week said were gross violations of human rights “on a massive scale.” More than 1.3 million people have fled their homes, and aid officials fear that mass hunger will set in later this year.

“Big news from Addis,” Toby Lanzer, the top UN aid official in South Sudan said on Twitter on Saturday.