UN aid operation for Darfur gains pace as Sudan eases access.

GENEVA, May 25 (AFP) -- International aid for hundreds of thousands of displaced people in Sudan's strife-torn Darfur region is gaining pace after the authorities in Khartoum eased access to the region, UN aid agencies said Tuesday.

But aid workers face a race against time to reach many of the victims of one of the world's worst humanitarian crises before the rainy season makes roads impassable in some areas in the next few weeks.

After months of blockages, the World Food Programme (WFP) said it was aiming to deliver about 14,500 tonnes of food this month for 800,000 people in the area.

"The roads are open again," said WFP spokeswoman Christiane Berthiaume.

"We have better access to the region since the ceasefire, we can reach more territory and more people, and above all it allows us to evaluate the situation better," she told journalists.

The warring sides in Darfur -- rebel groups and the Khartoum government, which is fighting alongside an Arab militia group -- reached a ceasefire pact at talks mediated by Chad in Ndjamena last month.

The UN Children's Fund (UNICEF) warned that although it had managed to double the number of people receving clean water to 300,000 in recent weeks, about 700,000 more people were barred access to safe wells or water supplies.

"It's a bit of a race against time. At the moment there is no water because it's the end of the dry season and people are dying of thirst," UNICEF spokesman Damien Personnaz said.

"In two or three weeks it will be the beginning of the rainy season and there will be too much water, but of bad quality," he added, warning of a likely surge in diarrheal diseases.

The Sudanese government has faced mounting international anger over the humanitarian crisis in Darfur, which the United Nations describes as the worst in the world.

An estimated 10,000 people have been killed and more than a million people driven from their homes, after the government adopted a scorched earth policy to tackle a rebellion by members of the Fur, Massalit and Zaghawa black African minorities in February 2003.

Berthiaume warned that the region was likely to be dependent on food aid for about 18 months because this year's harvest in the more fertile western part of Darfur had been abandoned after farming communities fled attacks by Khartoum and its ally, the Arab Janjaweed militia.

With convoys taking up to five or six days to reach their destination in the huge, mainly desert, area, WFP was airlifting supplies in some cases and was planning airdrops of food for more remote locations, she added.