More than a million hungry Somalis urgently need food aid due to worsening drought and conflict, a 20 percent increase since January, the U.N. said on Tuesday.
It is the first time that the number of Somalis in crisis has increased since the 2011 famine, in which 260,000 people died, the U.N. said.
"Concerted efforts are urgently required to save lives and prevent a free fall," U.N. humanitarian coordinator for Somalia Philippe Lazzarini told a news conference.
The famine was caused by drought, conflict and a ban on food aid in territory held by the Islamist militant group, al Shabaab.
In 2014, similar factors are at play. Two failed rains have resulted in poor harvests, surging food prices, water shortages and livestock deaths. The August harvest is estimated to be 37 percent below average following delayed and erratic March to June "Gu" rains, which Somalis rely on to grow their crops and water their livestock.
Conflict has cut off trade routes and access to seasonal agricultural work, which poor families rely upon to buy food.
"In urban areas that came under government control following the military offensive against insurgents in March 2014... access roads remain under insurgent control and trade flow is largely blocked, resulting in sharp increases in staple food prices," the U.N. Food Security and Nutrition Analysis Unit (FSNAU) said in a statement.
African Union-backed government troops have captured many towns in south-central Somalia from al Shabaab over the last three years, but the militants still control swathes of countryside.
"Aid organisations began using air cargo flights to areas with no road access. However, it is simply not sufficient to deliver the volume of humanitarian assistance required," said Lazzarini.
"Securing road access for commercial and humanitarian supplies in addition to having more resources is indispensable to the sustained delivery."
In Wajid in Bakool region, cereal prices have quadrupled since January, the FSNAU said, while doubling in other areas like Bakool's Hudur town.
There are 1,025,000 Somalis in phases three (crisis) and four (emergency) of the Integrated Food Security Phase Classification, used by experts to monitor hunger crises, where phase five equals famine.
Of these, 62 percent are internally displaced, while 27 percent are rural and 11 percent urban residents.
Nearly one in seven children under five (218,000 children) are acutely malnourished, up by 7 percent since January. This includes 43,800 severely malnourished children who risk death without treatment.
The next rains are due in October.