Aid agencies in Chad are preparing for a possible influx of tens of thousands of refugees from Darfur as fears grow that Sudan's expulsion of major relief organisations will escalate the humanitarian crisis there.

Some aid workers in Chad said agencies were making contingency plans for up to 100,000 new arrivals from the war-torn region in western Sudan. But they stressed it was too early to tell if there would be a major exodus.

Sudan kicked out 13 international aid agencies last week after the International Criminal Court issued an arrest warrant for President Omar Hassan al-Bashir for war crimes in Darfur.

Aid workers fear the move could prompt refugees to cross into Chad as food, water and medical supplies dwindle. They also say people could move if insecurity worsens now that the relief groups have left.

"It's really speculative to even guess how many might come at this point," one aid worker in Chad said. "We are looking at what may happen - we're looking at 50,000 to 100,000 - but I don't think it will happen for a couple of months unless insecurity increases."

Aid workers said people wanting to move would do so by June or July when the rainy season makes the border hard to cross.

"If the humanitarian situation deteriorates, and I think it will, people may take a decision to move before the rainy season - you might get 10,000 or 20,000 who come over at a time," the aid worker said on condition of anonymity.

The expelled agencies carried out about half of all relief work in Darfur, where some 4.7 million people receive aid. They say their presence on the ground also acted as a deterrent to the warring parties. Some fear their departure could now lead to increased insecurity.

VOLATILE REGION

U.N. agencies and relief groups are holding talks in Chad on contingency plans. Around 40 international agencies work in 12 refugee camps in eastern Chad, which shelter 250,000 people who have already fled Darfur.

Aid agency CARE said it could take in another 20,000 to 40,000 people in the three camps it manages, but it was too early to say what might happen.

"It's really going to depend on whether or not the remaining NGOs (non-governmental organisations in Darfur) are able to or allowed to upscale their operations," spokesman Kieran Green said.

"If the supplies start running out before the rainy season that's when we'll see whether movements are going to occur. We are still holding on to the hope that the government of Sudan will let us back in."

International Rescue Committee (IRC), which has also been thrown out of Sudan, said it was ready to scale up health care, water and sanitation services in Chad if there were new arrivals.

IRC regional director Kurt Tjossem said the expulsion of relief organisations had "decimated the international aid effort in Darfur".

"As life-saving services in some camps diminish, people may start searching for assistance elsewhere," he added.

"Initially families may move relatively short distances to other camps that still have services, but it's possible that refugees could travel farther and cross borders. The IRC is putting contingency plans in place in Chad as a precaution."

The U.N. refugee agency UNHCR said it already kept emergency supplies in Chad to cater for an extra 50,000 arrivals because the region is so volatile. It said it could easily fly in additional stock, including plastic sheeting, jerry cans and blankets, if needed.

But even in a worst-case scenario, aid workers do not expect Darfuris to arrive from major camps like Kalma in the south because it is too far away. Kalma, home to 90,000 people, is one of the most volatile camps and there are fears of a meningitis epidemic now that agencies providing medical services have been kicked out.

The people most likely to cross into Chad are those in camps in West Darfur and others living near the border. There could be an influx if there are security problems near West Darfur's capital El Geneina, which is close to the border. And there are Chadian refugees in Darfur who might also return.

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