Earlier, junta leader Senior Gen. Than Shwe had refused to take telephone calls from Ban and had not responded to two letters from him, Montas said. Holmes, who arrived in Yangon on Sunday, was to deliver a third letter about how the U.N. can assist the government's immediate and long-term relief effort.

Amanda Pitt, a U.N. spokeswoman in Bangkok, said the world body was seeing "some progress in terms of pipelines starting to come through" but that the aid operation was still unsatisfactory.

"Clearly we're still not satisfied, which is why we keep saying we need to upscale the response. We're not satisfied with it, nobody is. We can see the situation is terrible," she said.

At least 78,000 people were killed in the May 2-3 storm and another 56,000 were missing. The situation remained grim in the Irrawaddy delta south of Yangon.

In the delta city of Laputta, hundreds of children covered their heads from the rain with empty aluminum plates as they lined up in front of a private donation center on Sunday. They were given rice, a spoonful of curry and a potato.

"Children only. Please. Children only," shouted a man who pushed back a crowd of adults. He explained they were feeding children and the elderly first because food supplies were limited and most adults could still fend for themselves.

The relief effort has been impeded by a lack of logistical support, said Ramesh Shrestha, head of the U.N. Children's Fund in Myanmar. He said there are not enough trucks to transport supplies and a shortage of manpower to load and unload them.

"Many of those areas are still inaccessible because of the high water table, roads covered with fallen trees and bridges that are broken. The government has been clearing it but it's still not completely done yet," he said.

European Union nations have warned the junta could be committing a crime against humanity by blocking aid intended for up to 2.5 million survivors faced with hunger, loss of their homes and potential outbreaks of deadly diseases.

But signs have appeared that the generals might be listening to the chorus of criticism.

A team of 50 Chinese medics arrived in Yangon on Sunday night, following in the footsteps of medical personnel from India and Thailand, the official Chinese news agency Xinhua reported. On Monday, some 30 Thai doctors and nurses began working in the delta.

Myanmar's state-run media has lashed out at critics of the regime's response to the disaster, detailing the junta's efforts. State television showed Than Shwe inspecting supplies and comforting homeless victims in relatively clean and neat rows of blue tents.

The media said Than Shwe traveled from the capital, Naypyitaw, to relief camps in the suburbs of Yangon.

Some survivors clasped their hands and bowed as he and a column of military leaders walked past.

The official New Light of Myanmar newspaper said the government's National Disaster Preparedness Central Committee will work with foreign aid agencies "to ensure that all relief funds and supplies reach the storm victims."