Health experts warned that a "second disaster" loomed from diseases such as diarrhoea and malaria, even if survivors do manage to find food and shelter.
"This is the second disaster," Greg Beck, Southeast Asia programme director for the International Rescue Committee, told Reuters. "First was the cyclone and the surge of water, the second will come if there is no access to food, water and shelter. They will start dying," he said.
Official Burma media on Saturday revised the death toll to 23,335 people dead and 37,019 missing.
The generals approved one U.S. aid flight, due to arrive as soon as Monday carrying water purification systems and supplies to ward off waterborne diseases, U.S. officials said.
The U.S. Navy is sending four ships on exercises in Thailand towards Burma. France said it was sending a naval ship carrying heavy-lift helicopters and 1,500 tonnes of aid, which would arrive by the middle of next week.
The Americans say they are preparing the same kind of assistance they provided after the 2004 Asian tsunami and the 2005 Pakistan earthquake. But the air bridge the U.S. military set up during the tsunami is unlikely to be replicated.
"FOREIGN INTERFERENCE"
Myanmar has long been suspicious of the outside world, which the junta fears could bring in destabilising ideas and values, such as Western concepts of democracy and human rights.
The junta has brutally suppressed any sign of dissent. At least 31 people were killed when troops crushed monk-led pro-democracy protests last September.
While impervious to Western economic sanctions, the generals have avoided total isolation by using Burma's vast natural gas reserves to befriend energy-hungry China and India.
Burma's top General Than Shwe made his first public appearance since the cyclone, casting his ballot in the new capital of Nyapyidaw. Voting in cyclone-devastated areas, including Yangon, has been postponed for two weeks.
State-run TV warned of "foreign interference" in a broadcast message urging people to vote yes for the constitution.
Most people were expected to do just that. Of the 20 people Reuters interviewed near polling stations in Hlegu, only two admitted to voting no. Even then it was in a whisper and with a nervous glance over the shoulder first.
