CAIRO, June 13 (AFP) -- The United Nations Children Fund will request the international community for additional support to fund its operations in the war-raved Darfur region of west Sudan, the agency said.

This followed a visit to Darfur by UNICEF Executive Director Carol Bellamy, who toured camps for displaced persons there and met the people worst affected by the conflict in the region, including women and children.

Darfur is in the throes of what the United Nations calls the world's worst humanitarian crisis, prompted by a rebellion with ethnic overtones sparked in February 2003 that led to a fierce retaliation by government forces and allied Arab Janjaweed militia.

"She has seen the real hardship these people are living in," James Elder, of the UNICEF news desk in Nyala, told AFP following Bellamy's visit to a camp in Kass, a town north east of Nyala, capital of South Darfur state.

Bellamy's visit came after UNICEF had already revised upwards -- from 33 million to some 40 million dollars -- an initial appeal for funds for its activities in Darfur.

Elder said that Bellamy will now go back and seek additional assistance. "That's very necessary," he pointed out, adding that the agency was saving lives and could save more but "that can only be done with greater resources."

Kass used to have a population of about 30,000, but that has doubled in the past six months due mainly to an influx of people fleeing the ravages of the bitter conflict in the surounding villages, according to UNICEF.

This has stretched available resources and forced agencies operating in the area such as UNICEF to summon additional resources.

Bellamy spent the day meeting with children, women and elders in the camp and listening to their "primary concerns", Elder explained.

Her visit came as UNICEF warned that half a million children were in danger in Darfur.

The purpose of the visit was to enable her to "see first-hand the life- threatening situation facing hundreds of thousands of children caught in one of the world's most rapidly developing humanitarian crises", UNICEF said.

The agency said it was "deeply concerned about the growing vulnerability of the vast displaced population in Darfur, now estimated at some one million people, half of them children."

Nearly all face food shortages, outbreaks of disease, exploitation, and the rainy season, which has just started.

"That's a nasty scenario," Elder noted.

Bellamy had arrived in Nyala on Sunday at the start of a two-day tour of the region of west Sudan.

She and her delegation went straight into a meeting with the governor of South Darfur and senior government officials in the region. The party then traveled to Kass.

On Monday, the UNICEF head is to visit Geneina in West Darfur and return to Khartoum for talks with government officials.

UNICEF is currently focusing on providing access to safe drinking water, primary health care, shelter material, education and hygiene kits for families.

A major campaign to immunize more than two million children between the ages of nine months and 15 years against measles is underway in the region.

The European Union, United States and United Nations have all urged Khartoum to rein in the Janjaweed, while Sudan has dismissed charges that ethnic cleansing is being carried out in the region.

The conflict has forced more than 120,000 people to flee across the border into Chad, according to UNICEF.