1.5m Burmese in danger - Oxfam

The charity's regional chief, Sarah Ireland, said "there are all the factors" for a public health catastrophe.

The death toll from the May 3 cyclone is likely to be 100,000, she said, and that number could eventually multiply by 15 times. She told reporters: "We are afraid there is a real risk of a massive public catastrophe waiting to happen in Myanmar (Burma). It is a perfect storm, if you will."

Although overwhelmed by the worst disaster in Burma's recent history, the junta has turned down foreign help and insists on using its own infrastructure and poorly-equipped army to conduct a grossly mismanaged relief operation for some two million people in distress.

"There are certainly parameters around whatever we do. It is very sensitive politically, but within those parameters we are getting through," said Tim Costelloe of World Vision in Rangoon, one of the few foreign aid workers allowed in.

Aid workers said critical supplies were reaching Labutta, a town of 20,000 people whose population more than doubled with 30,000 refugees streaming in from dozens of surrounding villages devastated in the cyclone on May 3.

But efforts to get food and medicine from Labutta to lower-lying parts of the delta that were hardest hit have been slowed by the army's intense micromanaging.

"The government wants total control of the situation although they can't provide much and they have no experience in relief efforts," said a leading aid worker for an international aid organisation. "We have to report to them every step of the way, every decision we make.

"Their eyes are everywhere, monitoring what we do, who we talk to, what we bring in and how much," the aid worker said in a whisper, constantly looking around nervously as his assistant turned off all the lights except one dim lamp.

"Sorry, sorry. We don't want them to see you here. They don't trust us, as it is," he told a foreign reporter in Labutta.