KHARTOUM, Sudan (CNN) -- The threat of a major famine has been staved off in a key southern city but the region will need sustained aid for months to come, U.N. relief workers said on Thursday.

The U.N. World Food Program said that the situation in the south's second largest city of Wau had significantly improved, compared to July, when dozens of famine victims died daily.

"The area is out of the intensive care unit but it is still in a hospital ward," said WFP representative Mohammed Saleheen.

"Wau needed 1,500 metric tons of relief aid every month and that is what it has received since August," Saleheen said.

Sudan's Islamist government and the rebel Sudan People's Liberation Army (SPLA) agreed to a three-month cease-fire in the Bahr al-Ghazal region in July to let relief goods flow to the famine-hit area. They extended the truce for three months on October 14.

"The Bahr al-Ghazal region required 15,000 metric tons every month, which was also delivered," Saleheen said.

The WFP official said U.N. agencies and other relief groups would keep delivering food to the area for at least another year because fighting and population movements had disrupted farming.

Thousands dependent on aid

About 70,000 people are completely dependent on WFP food in Wau, the principal city in the Bahr al-Ghazal region.

A doctor in Wau, working for the medical relief group Doctors Without Borders, said by telephone there were now hardly any deaths from hunger, whereas in July 40 to 50 people a day were dying from starvation and disease. Admissions to hospitals had dropped and many hospital beds were empty, he added.

Wau was at the center of a famine that affected several parts of the south. An influx of villagers fleeing fighting between government troops and SPLA rebels worsened the crisis.

By late July, the population of Wau, 950 kilometers (600 miles) south of Khartoum, had swelled to more than 700,000 from its normal 150,000 or so.

U.N. relief brought aid to desperate people in southern Sudan

New crisis beginning

Saleheen said a new humanitarian crisis was building in Juba, the south's largest town, because of clashes between government troops and the SPLA rebels in Eastern Equatoria.

"The recent fighting has driven many people to Juba and many people in the town will be totally dependent on relief aid for some time because they have no land to cultivate and no cattle to live on as they have lost everything," Saleheen said.

He added that rainfall in the region had started late this year and floods had also damaged harvests.

About a sixth of Juba's 250,000 people are entirely dependent on WFP food aid.

A convoy of seven barges chartered by WFP left the northern river port of Kosti on November 30 for Juba with 2,500 tons of food and was expected to arrive in early January.

Reuters contributed to this report.