Officials say a massive cyclone that devastated Burma this weekend may have killed more than 15,000 people, eclipsing earlier estimates and making it the worst natural disaster to hit the country in modern history.

Burmese officials gave the latest death toll number to the Chinese news agency Xinhua. Initial reports had suggested anywhere between 4,000 and 10,000 people had died.

The official death toll has steadily climbed as officials reach isolated areas where Cyclone Nargis struck the hardest.

CNN reports that the last record-breaking natural disaster to devastate Burma came in 1926, when a wind storm killed 2,700 people.

On Monday, criticism is beginning to emerge about the government's reaction to the latest catastrophe.

"The government misled people. They could have warned us about the severity of the coming cyclone so we could be better prepared," said grocery store owner Thin Thin.

UN officials say hundreds of thousands of people in the affected areas need food, clean water and emergency shelter.

On Monday, residents of Yangon, the country's commercial capital, were using candles instead of electricity and lining up to purchase emergency supplies of water.

The country's secretive military junta, which spurned international aid after the 2004 tsunami disaster, told the UN it would accept help this time.

Canadian aid

Canada says it will offer up to $2 million in humanitarian assistance. In a press release, foreign affairs said it would provide cash contributions to Canadian International Development Agency (CIDA) partners in Burma.

The UN said earlier it is prepared to move quickly.

"It is a question of identifying stockpiles of plastic sheeting, of water purification tablets and other items, either within the country or in the region and ensuring they arrive as quickly as possible," Richard Horsey of the UN Office for the Co-ordination of Humanitarian Affairs said Monday in Bangkok, Thailand.

Thai officials announced that their country, which shares a border with Burma, would fly in a planeload of emergency assistance on Tuesday.

But the country appears to be slow to accept an offer of assistance from the U.S. State Department's Disaster Assistance Response Team.

"We have a DART team that is standing by and ready to go into Burma to help try to assess needs there," deputy spokesman Tom Casey said.

"As of this moment, the Burmese government has not given them permission, however, to go into the country. So, that is a barrier to us being able to move forward."

In a media release, Foreign Affairs Minister Maxime Bernier called on Burma's government to "provide full and unhindered access to humanitarian organizations to allow them to assist with the relief efforts."

'Torn to shreds'

"They've never seen a storm like this," World Vision official James East told Newsnet on Monday from Bangkok about the impact of the cyclone on Burma.

"We know the full force has really struck in an area where people are living in homes with thatched roofs and bamboo walls. So we expect the damage to be worse than in Yangon," where the storm toppled huge trees, he said.

"Likely the homes will have been torn to shreds, they would have lost all their dry food, and they likely have injured family members. So they've likely lost everything," East said.

World Vision has been distributing rice and water on the outskirts of Yangon, he said.

Government officials have asked for help such as chainsaw, roofing, medicines, and tarpaulins, he said.

In addition to the damage in the capital, five states -- Yangon, Irrawaddy, Bago, Karen and Mon -- have been declared disaster areas, reported Myaddy television, which is operated by the military.

The military has controlled Myanmar since 1962 and has been blamed for wide-spread human rights abuses and violent crackdowns on pro-democracy activists. Nobel Peace Prize laureate Aung San Suu Kyi has been under house arrest for nearly 12 of the past 18 years.

Former Swedish cabinet minister Jens Orback told reporters in Bangkok that what struck him was the absence of police or soldiers on the streets after the cyclone ended.

"It was private people cleaning up, it was monks out with machetes but no military, no police," he said.

East said in Pakistan, the military played an important role in helping aid efforts after a devastating 2005 earthquake in Kashmir.

"We would be looking to the military in terms of providing assistance and aid (in Burma)," he said.

With files from The Associated Press