UN Secretary General Ban Ki-moon has expressed his “immense frustration” at Burma’s slow response to the cyclone that hit the country nine days ago.
Mr Ban said aid had been able to reach less than a third of all those at risk. He said he had still not been able to speak to the leader of Burma’s military government, General Than Shwe.
The official toll for the cyclone has risen to almost 32,000, although foreign aid workers say the real number of dead may be much higher.
A BBC reporter in Burma says that while major cities are being cleaned up, many areas along Burma’s coast are still untouched by the rescue effort.
Unless those people get help soon, they will die, and many could be dead already, our reporter says.
‘Critical point’
Mr Ban said on Monday that the reaction of the regime of Burma – also known as Myanmar – to the cyclone had been “unacceptably slow”.
“We are at a critical point. Unless more aid gets into the country very quickly, we face an outbreak of infectious diseases that could dwarf today’s current crisis,” Mr Ban said.
“I therefore call in the most strenuous terms on the government of Myanmar to put its people’s lives first.”
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An aid worker’s account of conditions in Burma’s Delta region
Earlier on Monday the first US aid flight was allowed to land in Rangoon, after days of negotiation.
The US said it had permission to send in two further flights, and was offering an extra $13m in aid for Burma.
The plane was carrying 12,700kg of supplies including mosquito nets, blankets and water.
In addition, aircraft from medical relief agencies Medecins Sans Frontieres (MSF) and Medecins du Monde (MDM) arrived, loaded with a total of 56 tonnes of aid.
UN humanitarian head John Holmes said there had been “some slight improvement again in the last few days, particularly in the last 24 hours.”
Thirty-four visas for UN staff were being granted or expected to be granted, he said.
But he added that this was “clearly nothing like enough for the scale of the problem we’re trying to deal with”.
Dire conditions
In the Irrawaddy delta, the area worst affected by the cyclone, people have been left without shelter, crops, and stored rice.
With little access to food or clean drinking water, they face cholera, fever and other illnesses.
One aid worker for Operation Blessing told the BBC that the handful of aid organisations already on the ground had been able to distribute aid normally.
But he described the aid that was reaching people as only a tiny part of what was needed.
Aid agencies have warned of serious logistical hurdles in getting supplies to affected areas.
Roads and bridges have been washed away, and heavy rain that fell on Monday is expected to further complicate relief efforts.
Mr Ban said the UN had been able to reach some 270,000 people, providing only “the most rudimentary assistance”.
He said that food aid provided so far might amount to less than a 10th of what was needed and that rice stocks were “close to exhaustion”.
The EU is to hold an emergency meeting on getting aid to Burma on Tuesday..