More than 43,000 people have died since a deadly cyclone ripped through Burma earlier this month, state television reported Thursday, as government officials threatened action against those who interfered with the delivery of aid.

The latest death toll from Cyclone Nargis, which tore into the southeast Asian country on May 3, jumped by 5,000 since the last figure was released by Burma's military government Wednesday evening.

It was still well below the United Nations estimate of more than 100,000 killed, or a recent tally by the International Red Cross that puts the figure between 68,833 and 127,900.

The UN says an estimated 1.6 million to 2.5 million people who survived Cyclone Nargis are in danger of disease and starvation. (CBC)

The updated toll was released just hours after the ruling military junta threatened legal action against those who were discovered trading or hoarding international aid, the regime's first tacit concession that there were problems dispersing relief. Recent reports indicate foreign aid is being sold in markets and siphoned off by the army for its own purposes — a charge the government denied on state radio.

"The government has systematically accepted donations and has distributed the relief goods immediately and directly to the victims," it said.

BBC reporter Natalia Antelava, one of few foreign reporters who have gotten into Burma, reached the hardest hit area, the Irrawaddy delta, on a fisherman's boat, and said she saw no evidence any aid had reached the region, which still appears cut off from the outside world.

"I've counted one-hundred and seven and now I've lost count of the bodies I've passed," Antelava said. "They're everywhere along the banks of the river."

In one village she visited, 20 survivors were huddled in the only remaining structure among the wrecked houses where 400 people had lived. The survivors had subsisted on captured rainwater and a meagre amount of rice for the 10 days since the cyclone hit, she reported.

One of the survivors said that for days, government helicopters flew over the remnants of their village.

"We waved and shouted, but nothing happened," the woman said.

Criticism over blocked aid, referendum

The Burmese government has come under heavy criticism in the aftermath of the cyclone, accused of dragging its heels on providing aid to the estimated 1.6 million to 2.5 million survivors and neglecting their needs in favour of going ahead with a nationwide referendum last Saturday.

Results announced on state radio Thursday indicated voters had overwhelmingly chosen to adopt a pro-military constitution, which critics say is a sham document designed to increase the junta's power. It was approved by 92.4 per cent of voters, according to state radio, which reported a whopping 99 per cent of the 22 million voters turned out for the May 10th vote.

Voting in the hardest-hit areas of Rangoon and the Irrawaddy Delta has been postponed until May 24; however, the outcome will be largely symbolic as the government only needed a majority of the 27 million total eligible voters to approve the constitution.

"To everyone in the delta — in the 47 affected townships where the vote is being delayed — this is basically saying you might as well not turn out," said David Mathieson, a spokesman for Human Rights Watch in Bangkok.

The government's announcement that its constitution had been approved is insulting to the people of Burma, he said.

"There is simply no way that 92 per cent … would have voted 'yes' on a document that they know very little about and that most have never read," Mathieson said.

His concerns were echoed by observers in Canada, who criticized the vote during a press conference in Ottawa Thursday morning.

"We are deeply troubled by the referendum," said Kevin McLeod, a board member of the organization Canadian Friends of Burma. "From what we heard about the way it was handled, it was really a sham and basically a total travesty. People were forced to vote; ballots were printed with the 'Yes' already ticked; and in some cases [there is] evidence of mass intimidation."

Fraud, intimidation alleged at polls

Local journalists have cited instances of voter intimidation and fraud at polling stations, saying some officials asked voters to place their fingerprint on ballot papers or denied them privacy as they cast their vote.

The editor of a respected Burmese news magazine who had correspondents posted around the country said he had information that the vote was not totally free and fair.

"The essence of secrecy is totally lost in some of the polling booths," said the editor, who spoke on condition of anonymity for fear of reprisals.

Other journalists witnessed voters carrying three or four national registration cards, which they exchanged for an equal number of ballots, a violation of voting rules.

The constitution guarantees that 25 per cent of parliamentary seats go to the military, which has ruled Burma since 1962, while it allows the president to hand over all power to the armed forces in a state of emergency.

Constitution bars Aung San Suu Kyi from politics

It also prohibits the leader of Burma's pro-democracy movement, Aung San Suu Kyi, from entering public office. Her National League for Democracy party won the 1990 general election, but the military government refused to honour the results.

The junta has promised a 2010 general election following the constitution vote. Burma has not had a constitution since 1988, when the army brutally suppressed pro-democracy demonstrations and quashed the existing constitution.

Two days before the May 10 referendum, UN Secretary General Ban Ki-moon urged Burma to delay the vote and focus its attention on helping citizens recover from the cyclone.

The junta has allowed the UN and some other agencies to distribute aid but is refusing to allow foreign workers to leave the main city of Rangoon.

"There is a visible fence around Rangoon that we don't dare cross. A circle has been drawn around Rangoon, and expats are confined there," said Tim Costello of the aid group World Vision.

"While you are getting aid through, it's like getting it through on a three-inch pipe, not 30-inch pipe."

However, Ban said he has now secured support from Burma, its neighbours and key donors to increase the flow of cyclone relief aid and to convene a possible donors' conference this month.

Canada is flying 2,000 emergency shelter kits to the area that will be distributed by the International Red Cross after the flight arrives in Thailand on Friday.

The junta is also permitting 160 relief workers from India, China, Bangladesh and Thailand to enter Burma, though it was not clear if anyone but the Thais would be permitted to go to the most ravaged parts of the delta.

An emergency rapid assessment team from the Association of Southeast Asian Nations is also heading into Burma to assess the most critical needs.

With files from the Associated Press