The first UN plane carrying relief for the victims of Cyclone Nargis arrived in Burma today, six days after the devastating storm struck.
Shortly after it touched down, the US ambassador to the UN said he was "outraged" by Burma's continuing delays in allowing foreign aid agencies into the country.
Despite intense international pressure upon Burma's ruling military junta, disaster management experts still face long waits for entry visas and permission for supply flights to land has been slow in arriving.
Around 100 UN staff are still waiting for visas, while the US has yet to gain approval to begin military aid flights.
"We're outraged by the slowness of the response of the government of Burma to welcome and accept assistance," Zalmay Khalizad said. "It's clear that the government's ability to deal with the situation, which is catastrophic, is limited."
An estimated 1.5 million people have been "severely affected" by the disaster, John Holmes, the UN's chief of humanitarian affairs, said today. More than 100,000 people may have been killed and another 1 million left homeless.
Holmes spoke of growing frustration that visa delays were holding back the aid effort as the situation on the ground became "increasingly desperate".
"There is a real danger that an even worse tragedy may unfold if we cannot get the aid that's desperately needed in quickly," he said.
Shari Villarosa, the charge d'affaires of the US embassy in Burma, said there was a very real risk of disease outbreaks as the crisis continued.
"There may be over 100,000 deaths in the Irrawaddy delta area," she told reporters.
Huge areas of land are under floodwater, and up to 95% of buildings in Burma's largest city, Rangoon, are thought to have been destroyed.
The international development secretary, Douglas Alexander, today said the government was lobbying the Burmese ambassador in London about the need for "rapid access" to the country.
He said there had been "mixed signals" from the junta about accepting foreign help.
"The challenges of a disaster on this scale would daunt even the most developed country, and it is important the Burmese authorities accept all offers of international support offered to them," he added.
"The British government will continue to work to bring assistance and relief to the suffering people of Burma."
China, the Burmese regime's closest ally, today joined the calls for restrictions on overseas aid to be lifted.
Qin Gang, China's foreign ministry spokesman, said Beijing hoped Burma would "cooperate with the international community" and pledged another £2m to the relief effort.
"We hope Myanmar will … have consultation with the international community, and we hope Myanmar will overcome the disaster at an early date," Qin said, using the country name preferred by the Burmese authorities.
Aid agencies already operating in the country were working to find ways to get to some of the areas still swamped by floodwater.
Merlin, a medical aid agency, is converting a cruise ship into a floating hospital in order to get to survivors. The boat will be used to distribute clean water and medical supplies, and will also act as an emergency clinic.
"This boat will be a real life-saver," Merlin's chief executive, Carolyn Miller, said. "It … will be able to reach far more people far more quickly. This is vital, given that the risk of disease outbreaks heightens as every day passes."
Reports emerging from the affected areas suggested people were becoming increasingly desperate. Ray Hassan, from Christian Aid, said looting was breaking out.
"The indications are that the situation is getting increasingly tense and there is a sense that not enough is being done," he said.
"Communities are expecting assistance, and assistance isn't being provided. There is evidence of looting because people are desperate,"
Three more UN planes are expected to be given clearance to land later today.
Burmese state television screened pictures of the prime minister, Thein Sein, distributing food packages to the sick and injured and soldiers in helicopters dropping food over villages.
But as the scale of the humanitarian disaster continues to escalate, it is thought Burma does not have enough resources or expertise to cope.
"The UN has managed to get some assessment teams into the field, but we need the floodgates to open," Mark Canning, the British ambassador in Rangoon, said.
