Volunteers from Mercy Relief and Singapore Soka Youth Center pack relief supplies bound for cyclone-devasted Burma on Friday in Singapore. The supplies include tents, water purification tablets and medical supplies. (Stefen Chow/Associated Press)

UN Secretary General Ban Ki-moon urged Burma's military rulers Friday to allow international workers and aid into the cyclone-ravaged country "without hindrance," warning "inaction could be deadly" after nearly a week of delays.

Ban's comments came as the UN World Food Program said it will resume sending aid shipments to Burma on Saturday, after suspending efforts earlier Friday on accusations the military government there was seizing supplies intended for 1.5 million cyclone survivors.

The UN chief also said he has been unable to speak directly with any of the junta leaders directly since the devastating storm hit last Saturday.

"Regrettably I have not been able to contact them," Ban told reporters in Atlanta. "I am still trying to talk with them as well as with leaders in neighbouring countries."

Negotiations were underway Friday to release two shipments of high-energy biscuits being held by Burmese authorities, World Food Program spokeswoman Nancy Roman said.

In this photograph released by Democratic Voice of Burma on Friday, bodies of children killed during Cyclone Nargis lie in water in an unknown location in Burma. (str/Associated Press)

"The food has not yet been released," Roman told CBC News on Friday. "From our perspective, we just want to get it out as soon as we can."

Another WFP spokesman, Paul Risley, said all food aid and other supplies delivered by the WFP, whose four planes touched down in Burma for the first time Thursday, had been confiscated by the ruling military junta. More than 34 tonnes of high-energy biscuits were said to be among the supplies.

Risley said he didn't know why the supplies had been seized, but the move had left the WFP with "no choice" but to suspend its aid shipments to Burma, also known as Myanmar.

The Burmese government said Friday it had taken control of the shipments of relief supplies in order to distribute them across the country, but denied seizing the materials.

"I would like to know which person or organization [made these] these baseless accusations," government spokesman Ye Htut said in a statement e-mailed to the Associated Press.

A relief plane from Qatar was able to drop off supplies in the southeast Asian country Friday, but humanitarian workers and journalists on board were turned away. Foreign Ministry officials said the flight was sent back after landing in Rangoon because the search-and-rescue team and media on board had not received permission to enter the country.

Burmese officials released a statement Friday expressing gratitude for the 11 planes loaded with supplies that have landed in the country, but urged agencies to send materials rather than personnel.

Visa delays 'unprecedented'

Meanwhile, U.S. officials said Friday that the junta has agreed to allow a single U.S. cargo aircraft to bring in relief supplies, but the top U.S. diplomat in Burma said she was told by regime officials that they not ready to let in American aid workers.

Late Thursday, Burma rejected an offer from the U.S. to send transport planes packed with supplies into the country. The planes were waiting in neighbouring Thailand for permission to enter.

Earlier Friday, Risley called the refusal by Burma's isolationist junta to give visas to relief workers looking to help victims in the cyclone-ravaged country "unprecedented in modern humanitarian relief efforts."

An elderly Burmese woman lies waiting for help in a hut in Kun Chan Gone township, near Rangoon, following last weekend's devastating cyclone. (Democratic Voice of Burma/Associated Press)

He said the organization has submitted 10 visa applications around the world, including six in Bangkok, but none have been granted.

Humanitarian agencies fear delays in issuing visas to relief workers could push the death toll from last Saturday's cyclone above 100,000 as victims run out of safe drinking water and food. The official death toll is pegged at more than 23,000, while at least 37,000 are missing.

"The military government has said that they don't need any expertise on the ground, they are adamant about this, so now it's really a stalemate here and people are really wondering how desperate [things] are going to get," the CBC's Michel Cormier reported from Bangkok on Friday.

Both American and French officials have raised the idea of dropping aid into Burma unilaterally, without permission from the ruling military junta. French Foreign Minister Bernard Kouchner, co-founder of the aid group Doctors Without Borders, said this week that unauthorized air drops could be permitted under the UN's "responsibility to protect" mandate, which applies to civilians.

Such an approach, however, raises both political and practical problems, especially regarding how the aid would then be distributed among survivors.

"How would you in practice deliver supplies to individuals and families if the authorities of the country don't want that to happen? I think that raises many, many issues," said Richard Horsey, a Bangkok-based spokesman for the UN Office for the Co-ordination of Humanitarian Aid.

UN reaches 276,000 survivors

Burmese villagers work in a town devastated by last weekend's cyclone in Twantay township, southern Burma. (Associated Press)

He said the UN and its partners have been able to reach 276,000 of the more than 1.5 million people affected by Cyclone Nargis as of two days ago, and more have been assisted since then. While foreign aid workers have not been banned outright, he said, key UN personnel are still waiting for the green light to enter the country.

"It's more than just getting resources to Rangoon, it's more than just getting supplies there. We need to have the structures in place to run an efficient operation and the logistical capacity in terms of boats, and helicopters and so on to get it quickly out to the people who need it," Horsey said.

Reports have appeared of entire villages submerged, bodies floating in salty water and children searching for their families. A number of countries, including Canada, have urged the Burmese to allow relief workers in.

An official with World Vision Australia, Tim Costello, told CBC News on Friday that some aid was getting through to the country, and that money donated to the organization was being handled by the organization itself and not members of the military government.

Costello said the “working theory” amongst relief workers on the ground was that the Burmese government could begin to allow more international aid experts into the country after this weekend's referendum.

State radio has said Saturday's referendum on a proposed constitution, backed by the junta, would be delayed in areas affected by the storm, but the vote will take place in other places.

"The major problem now is that most of the military has been seconded to help in this referendum that will happen [Saturday] that's supposed to extend the power to the junta for another 10 years," Cormier said.

"So what the aid agencies believe here is that the government will not let anybody inside until that referendum is finished."

With files from the Associated Press