The U.N.'s top humanitarian official made fresh pleas to Burma's military government Tuesday to allow in more foreign aid for cyclone survivors, as the country began three days of mourning for the 134,000 dead and missing.

Flags at government offices, schools and large hotels in Burma, which has been renamed Myanmar, were lowered to half-staff. But shops were open as usual and many people in Rangoon said they had little idea of what the government-announced mourning entailed.

Some residents frustrated with the junta's response to the disaster called it a symbolic gesture that lacked sincerity.

"If they are sincere, they should welcome help from everyone," said Zin Moe, 32, who sells clothes. "They are not letting in aid quickly enough and people are angry."

Meanwhile, the U.N. announced that Secretary-General Ban Ki-Moon will meet the head of Burma's ruling junta during a visit this week to discuss assistance for cyclone victims and an inspection of the devastated area.

On Sunday, he is expected to attend a meeting of aid donors in Rangoon.

"This is a critical moment for Myanmar," he told reporters before heading to the airport. "We have a functioning relief program in place but so far have been able to reach only 25 percent of Myanmar's people in need."

He said he is confident that aid can be stepped up quickly and he welcomed the government's "recent flexibility" in allowing Asian relief workers under the auspices of the 10-member Association of Southeast Asian Nations to begin distributing international aid supplies.

The United Nations has received permission from Burma's government to operate nine World Food Program helicopters "which will allow us to reach areas that have so far been largely unaccessible," Ban said.

At least 1.7 million survivors of the storm are in desperate need of aid, including food, clean water and shelter.

The junta said Monday it would allow its Asian neighbors to oversee distribution of foreign relief to cyclone survivors.

But most foreign aid workers still were banned from the storm-devastated area and the United Nations said only 20 percent of the survivors had received some form of international assistance.

U.N. Undersecretary-General for Humanitarian Affairs John Holmes is in Burma to persuade its government to allow more in international assistance and pave the way for Ban's visit.

Holmes told reporters Tuesday that Ban will meet with Senior Gen. Than Shwe, the head of the country's ruling junta. Burmese officials were not immediately available to confirm the meeting plan.

The cyclone's official death toll stands at about 78,000, with another 56,000 people missing. Conditions in the low-lying Irrawaddy delta remain precarious, with survivors facing disease, malnutrition and exposure to the elements.

A Burmese doctor returning from the delta said refugees in the bigger towns were receiving some aid and medical care but expressed concern for those in outlying villages.

Villagers were still trickling into the towns because they had received no aid, she said.

"We saw one young girl yesterday. Her lips and her nails were blue. She looked like she was going to die," Tin Sein said on Tuesday. "People who haven't eaten or drunk clean water and also completely exposed to the rains and storm."

"I don't think anyone has a good picture right now of the overall situation," she said. "People give different facts and figures. It's a major problem."

State-owned media reported Tuesday that the head of the country's ruling junta met storm victims in the hard-hit Irrawaddy delta Monday, saying the regime had "promptly carried out rescue and rehabilitation tasks."

The general said the government has spent more than $45.5 million on relief operations, has met immediate needs such as food, shelter and health care and is moving into the reconstruction phase.

Foreign aid agencies and the United Nations were less upbeat. They said only some 500,000 of as many as 2.4 million storm victims have received some form of international assistance.

"It is clear that the emergency phase is set to continue for some time," the United Nations said.

Burma promised Monday it would allow its Asian neighbors to oversee the distribution of foreign relief to cyclone survivors.

In Singapore, an emergency meeting of foreign ministers from the 10-member Association of Southeast Asian Nations agreed to set up an ASEAN-led task force for redistributing foreign aid.

Burma agreed to open its doors to medical teams from all ASEAN countries, Singapore Foreign Minister George Yeo said. ASEAN member Thailand already has sent teams, as have non-ASEAN neighbors India and China.

Burma, one of the world's poorest nations, claims losses from the disaster exceeded $10 billion. But it may have problems funding a recovery.

World Bank Managing Director Juan Jose Daboub said Tuesday the bank will not give any financial aid or loans because Burma has failed to repay its debts for a decade.

Daboub said the World Bank is providing technical support to assess damage in Burma and help plan economic reconstruction.

"But the bank cannot legally provide any (financial) resources to Burma because it is in arrears with the bank since 1998," he said in Singapore.