Violence in Sudan's remote western region of Darfur has forced nearly a quarter of a million people to flee their homes this year, increasing the pressure on the humanitarian effort, the United Nations said in a report.

The International Committee of the Red Cross (ICRC) also expressed concern over worsening security conditions in Darfur.

"Over 240,000 people have been newly displaced or re-displaced during 2007," according to the report prepared by the UN Office for the Coordination of
Humanitarian Affairs (OCHA), in collaboration with partner UN agencies and NGOs. Thousands of people were fleeing their homes each week, the report added.

It came as the Sudanese government and Darfur rebels prepare for peace talks next month aimed at ending more than four years of conflict that has claimed an estimated 200,000 lives and displaced some two million people from their homes.

The UN said the insecurity was complicating efforts to respond to the needs
of the new internally displaced persons (IDPs) and the delivery of assistance to millions of people depending on aid.

"During August, the humanitarian situation in Darfur has deteriorated," said the report, the Sudan Humanitarian Overview. It added that attacks against humanitarian staff continued throughout the month.

"Seven humanitarian vehicles were hijacked or stolen, and four humanitarian convoys were attacked," the UN said.

"Five humanitarians were kidnapped or abducted, and three were physically assaulted," it added. "Many areas of Darfur still remain a hostile environment for relief efforts," the report said.

UN staff were forced to relocate on 24 occasions in 2007.

"This has a direct and tangible impact on the quality and quantity of aid and results, in some cases, in the inability to reach those in need," it said.

The ICRC has also raised concerns.

"Owing to the unstable and tense environment and the poor road conditions during the current rainy season, access to remote rural zones remains irregular and difficult," an ICRC statement said.

“The ICRC has determined that thousands of people, many of whom had already been displaced several times since the conflict began in 2003, moved to Dom Jong, Fujo, Fatma Karal, Kutrum, Kwila, Boldong, Kati and Kurifal in remote
areas of Western Jebel Marra between June and August," it observed.

"This means that the communities most at risk in rural areas are often reachable only sporadically," said the head of the ICRC's Darfur operation, Denise Duran, quoted in the statement.

"Many fled there to escape the fighting or out of fear of attack; others were forced to move by their deteriorating economic situation or their increasing isolation and lack of access to services in remote places," the ICRC said.

"This population movement affects the already fragile situation of residents and formerly displaced people in the region," it added.

Armed elements have also appeared in IDP camps, a presence which has been attracting the Sudanese security forces.

"In many IDP camps, armed elements are present, and violent incidents are
increasing," said the UN.

The organisation said that in August, "all operations were suspended in Zalingei Camp [West Darfur] for two days, while Kalma camp [South Darfur] was closed to aid operations for three days."

Rains that have been battering the country have also added new problems.

"Worsening sanitary conditions in the IDP camps have led to a spread of waterborne diseases. In some cases, this has been accompanied by worsening malnutrition rates which, although localised, have required and received
urgent responses," said the UN report.

Despite this, aid workers resumed food distribution to some 160,000 people who had not received assistance since May.

"However, 60,000 Darfurians were still not reached in July due to insecurity in some areas," the UN said. It added that humanitarian workers have not been able to access several parts of Jebel Marra in West Darfur since 16 August.

The UN Secretary-General, Ban Ki-moon, has called for an end to the ongoing violence.

The UN and African Union (AU) are in the process of deploying a joint force
of 26,000 troops in the region to replace the ill-equipped and cash-strapped AU mission that has been unable to stop the violence.