YANGON, Myanmar - Relief supplies from the United Nations have begun arriving in Myanmar.

But officials say U.S. military planes loaded with aid for cyclone victims are still denied access by the country's isolationist military government.

The junta is also continuing hold up visas for UN aid distribution teams amid fears that lack of safe drinking water and food could push the death toll above 100,000.

UN official confirmed Thursday that two airplanes carrying high-energy biscuits, medicine and other supplies had arrived in Yangon. Two other planes are to follow.

But Myanmar authorities have refused permission for U.S. military aircraft to fly in relief supplies.

The U.S. ambassador to Thailand, Eric John, says he thought such permission had been granted, but that does not appears to be the case. Thai Prime Minister Samak Sundaravej says he has offered to negotiate on Washington's behalf to persuade the junta to change its mind.

The U.S. military, meanwhile, sent more humanitarian supplies and equipment to a staging area in Thailand. A C-17 transport plane with water and food landed Thursday, joining the two C-130s in place, U.S. air force spokeswoman Megan Orton said at the Pentagon. Another C-130 loaded with supplies was on its way, she said.

The U.S. navy also has three ships participating in an exercise in the Gulf of Thailand that could help in any relief effort - the USS Essex, the USS Juneau and the USS Harper's Ferry - but navy officials said they are still in a holding pattern.

The Essex is an amphibious assault ship with 23 helicopters aboard, including 19 that are capable of lifting cargo from ship to shore, as well as more than 1,500 Marines.

In Yangon, a neighbour of Aung San Suu Kyi said in a telephone interview that the roof of the house where the democracy leader lives was partially blown off in the storm.

The neighbour added that the electricity to her dilapidated lakeside bungalow was also knocked out in the storm.

The Nobel Peace Prize laureate is using candles at night since she has no generator in her home, where she is held under house arrest, said the neighbour, who spoke on condition of anonymity because of the sensitivity of the subject.

It was not clear when difficulties over getting aid into Myanmar might ease.

Myanmar's generals, traditionally wary of foreign influence, issued an appeal for international assistance after the storm struck Saturday.

But they have since dragged their feet on issuing visas to relief workers even as survivors faced hunger, disease and flooding.

French Foreign Minister Bernard Kouchner and British Foreign Secretary David Miliband asked Myanmar's junta to "lift all restrictions on the distribution of aid."

The UN also called the government to let aid and aid workers in.

"It is imperative at this point that they do open up and allow a major international relief effort to get under way," Richard Horsey, who co-ordinates UN humanitarian aid out of Bangkok, told AP Television News.

The Association of Southeast Nations appealed to the international community to keep sending aid through Thailand.

"Please keep the help coming, keep the contributions coming, and if you have to, go to Thailand, park there and wait for redistribution from there," said ASEAN's secretary general, Surin Pitsuwan.

Myanmar's state media said cyclone Nargis killed at least 22,980 people and left 42,119 missing, mostly in the hardest-hit Irrawaddy delta.

But Shari Villarosa, who heads the U.S. Embassy in Yangon, said the number of dead could eventually exceed 100,000 because safe food and water were scarce and unsanitary conditions widespread.

UN officials estimated as many as one million people have been left homeless in Myanmar, which also is known as Burma.

Entire villages in the delta were still submerged from the storm, and bloated corpses could be seen stuck in the mangroves. Some survivors stripped clothes off the dead. People wailed as they described the horror of the torrent swept ashore by the cyclone.

"I don't know what happened to my wife and young children," said Phan Maung, 55, who held onto a coconut tree until the water level dropped. By then his family was gone.

The World Health Organization has received reports of malaria outbreaks in the worst-affected area, and fears of waterborne illnesses due to dirty water and poor sanitation remained a concern, said Poonam Khetrapal Singh, deputy director of WHO's Southeast Asia office in New Delhi.

"Safe water, sanitation, safe food. These are things that we feel are priorities at the moment," she said.

Even in villages near Yangon, the country's largest city that is home to more than million people, residents complained they have received no government assistance and were relying on meagre handouts from Buddhist monasteries.

"The government is not helping us. No aid is coming. There is no money, no rice," said Mu Sanda, one of some 50 people huddled in a monastery dining room converted into an evacuation centre in Kyauktan, 25 kilometres southeast of Yangon.

Even China, Myanmar's closest ally, urged the military junta to work with the international community.

The London-based human rights group Amnesty International said some donors were delaying aid for fear it would be siphoned off to the army.

The World Food Program's regional director, Anthony Banbury, indicated the United Nations had similar concerns.

"We will not just bring our supplies to an airport, dump it and take off," he said. "This is one reason why there is a hold up now, because we are going to bring in not just supplies but a lot of capacity to go with them to make sure the supplies get to the people."