The UN food agency suspended aid flights to cyclone-struck Myanmar on Friday after the military government seized two deliveries at Yangon airport, apparently determined to distribute supplies on its own.
The shipments of 38 tonnes of high-energy biscuits, enough to feed 95,000 people, were intended to be loaded on trucks and sent to the inundated Irrawaddy delta where most of the estimated 1.5 million victims need help.
"We're going to have to shut down our very small airlift operation until we get guarantees from the authorities that we'll be able to have the food when it arrives," UN World Food Programme regional director Tony Banbury said.
"I am furious. It is unacceptable." Governments around the world have been pressing Myanmar's ruling generals to open the country's borders to desperately-needed assistance and on Friday, Germany said it agreed with a proposal by France to use the UN Security Council.
The Myanmar government has stated its preference through the state-run media that it would accept "relief in cash and kind" but not foreign aid workers.