The Burmese authorities have sealed off the cyclone disaster zone from the outside world, expelling foreign aid workers and placing multiple checkpoints along roads into the Irrawaddy delta, to the despair of foreign diplomats and aid workers.

The move came as the UN reported that as many as 2.5 million people were thought to have been affected severely by the cyclone. The Red Cross reported that the death toll from the disaster could reach 127,990.

The isolation of the Delta confirms the growing sense among international organisations that the Burmese junta is never going to allow a massive foreign-led aid effort of the kind that was mounted in several countries after the 2004 Indian Ocean tsunami. Aid groups are trying instead to mount a stealth operation in which Western aid is distributed by government organisations, local aid workers, and international staff from countries which the regime regards as friendly and compliant.

Time, though, is running out - not only to avert epidemics of infectious diseases such as cholera, but also to prevent a catastrophic failure of this year's rice crop, 65 per cent of which comes from the cyclone stricken area.

The handful of foreign aid workers who had made it out to the stricken areas of the Delta were on their way back to Rangoon yesterday on the orders of the Government. Foreign journalists who attempted to reach the area were turned back at multiple military checkpoints.

One British NGO (non-governmental organisation), the medical charity Merlin, has been allowed to keep a foreign presence in the southwestern city of Labutta, where the organisation had a longstanding project. The rest, including UN organisations such as the World Food Programme and UN Development Programme, must rely on their Burmese staff.

Many of them are well trained and competent but, according to aid workers in Rangoon, experienced foreign experts are also required to oversee logistical planning and to operate technical imported equipment such as water purification plants.

Thirteen days after Cyclone Nargis, anger at the junta's refusal to allow large-scale foreign aid is giving way to resignation and a search for practical ways around its stubbornness. The heads of aid organisations based in Rangoon report that Cabinet ministers appear unhappy at the suffering inflicted on their people by the cyclone and willing to accept foreign experts. They have been overruled by the senior members of the ruling State Peace and Development Council (SPDC), above all the senior general, Than Shwe.

The Thai Prime Minister, Samak Sundaravej, had a two and a half hour meeting yesterday with the Burmese Prime Minister, Thein Sein, who ruled out a significant foreign presence on the ground. “He insisted that his country has a government, its people and the private sector to tackle the problem by themselves,” Mr Samak said.

“They are confident of dealing with the problem by themselves ... They don't need experts but are willing to get aid supplies from every country.”

Larger quantities of aid, including tarpaulins from Britain, came through Rangoon airport yesterday after the trickle of last week. The job of distributing these increased supplies is beyond the capacity of the Burmese military but, rather than being dominated by Western experts, the junta has proposed that the aid effort should be overseen by international staff from China, Burma's closest friend, from neighbouring India and Bangladesh, and from the Association of Southeast Asian Nations, a regional organisation that has failed consistently to censure the generals for all but their most extreme acts of oppression.

Even if such an arrangement were agreed, it would require intense organisation to save the next rice harvest. The five states most affected by the cyclone produce 65 per cent of the country's rice, and the Irrawaddy delta produces 15 per cent. Planting the new rice must take place within the next six weeks if there is to be a harvest in October.

The storm, apart from killing and displacing farmers and destroying villages, inundated fields with salty water, destroyed dikes and irrigation channels, and drowned 200,000 buffalo used to plough the fields. The Government has said that it will need $243 million for salt-resistant seed, fertilisers, ploughs and repairs.

The two million Burmese left homeless by Cyclone Nargis may be just hours away from the ravages of a second storm (Leo Lewis writes).

Citing a forecast by the Joint Typhoon Warning Centre (JTWC), the United Nations disaster response arm cautioned that a new cyclone may be forming around Burma and carried the risk of making landfall within the next 12 hours. The Hawaiian-based JTWC indicated that the storm may track towards the Burmese city of Rangoon, which is acting as the nerve-centre for the few international aid operations whose presence has been sanctioned by the junta. Its impact on the limited aid operations would be dire.

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