The famine gripping parts of southern Somalia has spread to three new areas of the country, with the entire south likely to be declared a famine zone within the next six weeks, the United Nations said Wednesday.

Acute malnutrition and death rates have surpassed famine thresholds in the Balcad and Cadale districts of Middle Shabelle and among the refugee populations in Mogadishu and the Afgoye corridor, according to a statement from the U.N. Food and Agriculture Organization’s Somalia food security unit.

The statement called the current humanitarian response “inadequate,” attributing to it “ongoing access restrictions and difficulties in scaling up emergency assistance programs, as well as funding gaps.”

Much of southern Somalia is controlled by al-Shabab Islamist militants who last year banned food aid and forced many aid groups out of the region, exacerbating the drought crisis.

Famine is expected to persist across southern Somalia until the end of the year, the statement said.

Each day, hundreds of drought-hit Somalis are streaming into squalid camps in and around the capital, Mogadishu, defying rebel orders to stay put and walking into a war zone.

The start of the Muslim holy month of Ramadan two days ago coincided with a new offensive by African peacekeepers and government forces against the insurgents and a jump in rebel suicide-attack threats.

The violence has compromised the delivery of emergency aid to some 100,000 refugees who have arrived in Mogadishu in the past two months, bringing the total to about 400,000.

“Local doctors came to us this morning and said two of my children are malnourished and anemic. We were given a few days worth of food but we have no shelter, not even plastic sheets,” said Hawa Omar, a mother of seven.

Omar spoke in a makeshift settlement near the airport that is home to an estimated 4,000 newly arrived refugees, about six miles from the front lines where government forces engage the rebels in daily gun battles.

She was among several camp dwellers who said that they had not received any help from international agencies, only from residents.

The U.N. refugee agency, UNHCR, said that it was able to distribute relief through local networks but that its work assessing the needs of new arrivals had been slowed.

“The plan was to start the assessments in about 10 other settlements in the coming days, but all the movement’s been restricted since the offensive started,” Andy Needham, spokesman for UNHCR Somalia, said in Nairobi.

Drought, conflict and a lack of food aid have left 3.6 million people at risk of starvation in southern Somalia. The drought, the worst in decades, has affected about 12 million people across the Horn of Africa.

The U.N. World Food Program welcomed a move by the United States on Tuesday to relax rules imposed on charities operating in al-Shabab-controlled regions of Somalia, with the intent of boosting the amount of relief reaching those areas.

When Washington placed the al-Qaeda affiliated group on its list of known terrorist organizations, aid groups whose operations accidentally benefited the rebels risked prosecution, analysts said.

“Certain organizations will be more relaxed. It should enable humanitarian aid to get closer to those who need it most,” said World Food Program spokesman David Orr, whose agency was forced to suspend operations in southern Somalia in early 2010.

Al-Shabab leaders have given conflicting signals about whether aid programs would be allowed to resume.

Orr said that the World Food Program, which still cannot operate in southern Somalia, remained concerned that food aid could end up in rebel hands if its distribution was not properly monitored.

— Reuters

Katy Migiro in Nairobi contributed to this report.