The European Union's Humanitarian Aid Commissioner Louis Michel says he has made no breakthrough on his two-day visit to Burma in convincing the country's military leaders to admit more foreign aid workers.

Speaking two weeks after Cyclone Nargis devastated Burma's southern delta region, Mr Michel said he was still seeking permission to visit the disaster zone, and said his requests for more international experts to be given visas "would be considered".

"They didn't answer the question, and they did not give any reason," he said.

"In a few days, if I have no concrete answer on all these questions, then I can put a judgement, but now I cannot."

The UN says at least 500,000 people are believed to be sheltering in temporary settlements in southern Burma.

Mr Michel said he had only been allowed to visit "a rather perfect, organised camp" outside the main city of Rangoon, hundreds of miles from the delta region.

The delta remains largely off limited to foreigners, with the Burmese military insisting that its own relief and rescue effort is sufficient to meet the needs of an estimated 2.5 million people left homeless by the cyclone.

Mr Michel unequivocally rejected that claim.

"They only pretend that everything is under control. They are of course happy with the aid that we are bringing," he said, referring to planeloads of supplies that have arrived from the international community.

UN humanitarian chief John Holmes is also waiting for a visa to travel to Burma where he hopes to continue the pressure on Burma's leaders to get aid to needy people before the region falls prey to starvation and disease.

State media say the official death toll has now passed 43,000, with nearly 28,000 still missing.

High level talks
The UN secretary general, Ban Ki-moon, is to convene an emergency summit with Burma's Asian neighbours on getting more aid into the delta region.

Members of the Association of South East Asian Nations (ASEAN) will also hold a special meeting on Monday in Singapore to discuss the crisis in Burma.

On Thursday ASEAN secretary general Surin Pitsuwan said ASEAN would also lead an international 'coalition of mercy' to provide aid to Burma.

Aid to Burma 'cannot be forced'
However Australian Ambassador to the United Nations Robert Hill says it is not possible for the international community to force Burma's military government to open its borders to foreign relief workers.

Mr Hill says coercive intervention is not being discussed at the United Nations.

"The world is frustrated and disappointed but there's not a serious discussion about a coercive response," he said.

"Basically states have the primary responsibility to address the needs of their peoples in these difficult times.

"It's good that others offer assistance, (but) whether it's accepted really depends on the national government in place at the time."

More bad weather
Earlier, weather experts said more heavy rain would fall in southern Burma over the weekend.

Meteorologists in India say a low-pressure system in the region could turn into another cyclone in the coming four days, compounding the misery of cyclone survivors.

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