UN blasts Myanmar for visa policy on aid workers

"The most dramatic situation is the case of children who have lost their parents. We don't know at the moment how many have lost their parents, relatives," said Juanita Vasquez, a representative of the U.N. Children's Fund in Myanmar.

Grim assessments about the immediate future continued: The aid group Action Against Hunger noted that the delta region is known as the country's granary, and the cyclone hit before the harvest.

"If the harvest has been destroyed this will have a devastating impact on food security in Myanmar," the group said.

In Yangon itself, the price of increasingly scarce water shot up by more than 500 percent, and rice and oil jumped by 60 percent over the last three days, the group said.

Hardships in the country's largest city have prompted some embassies, including that of the United States, to send diplomats' families out of the country.

Although the military regime had begun allowing in the first major international aid shipments, it snubbed a U.S. offer to help cyclone victims

By doing so, the junta refused to take advantage of Washington's enormous ability to deliver aid quickly, which was evident during the 2004 Indian Ocean tsunami that killed 230,000 people in a dozen nations.

The first foreign military aid following that disaster reached the hardest-hit nation, Indonesia, two days later. The most significant help came when U.S. helicopters from the USS Abraham Lincoln began flying relief missions to isolated communities along the Indonesian coast.

With roads in the Irrawaddy delta washed out and the infrastructure in shambles, large swaths of the region are accessible only by air, something few other countries are equipped to handle as well as the U.S.

Tim Costello, chief executive of World Vision Australia, said that "it's certainly the case that the Americans, as they showed in the tsunami, have extraordinary capacity."