Burma has tightened access to its cyclone disaster zone, turning back foreign aid groups seeking to bring aid into the country.
A top EU humanitarian official says there is now a real risk of famine, after the storm destroyed rice stocks in a main farming region in what is one of the world's poorest and most isolated countries.
International aid groups held an urgent meeting in neighbouring Thailand, frustrated by a defiant regime that has held up visas for emergency workers to deliver food, water, medicine and shelter for up to two million people.
But hope is fading that Burmese generals, deeply suspicious of the outside world, will make an exception.
'If there is a lack of access, more people will die,' warns Louis Michel, the EU's humanitarian aid commissioner.
'The fact that it is the rice bowl of Myanmar that has been hit and that all the stocks of rice have been destroyed - there is a risk of a catastrophe at the level of famine,' he said.
Even though the secretive generals may never allow the true scale of the catastrophe to become known, the regime itself says 62,000 people are dead or missing.
Aid groups say that while aid is flowing in - five more US aid flights arrived today - only experienced disaster specialists can ensure the vast relief operation work gets supplies to the neediest.
Mike Pattison, a logistics official from World Vision, said non-specialists could not set up large water purification systems or choose sites for food warehouses that can be defended in riots.
The UN has warned that the aid that is getting into the country, also known as Myanmar, is being diverted from those who need it most.
