UNITED NATIONS — With the death toll in Burma reportedly nearing 10,000 after the weekend’s cyclone, the ruling military junta appears to be tightening its grip on the country.

During a rare press conference, America’s first lady yesterday openly criticized the Burmese rulers’ handling of the crisis. Even as the leaders of the junta mull whether to accept outside help, they are refusing to reschedule a much-criticized referendum on their new constitution, planned for Saturday.

President Bush today is scheduled to award the Burmese opposition leader, Aung San Suu Kyi, the Congressional Gold Medal, and Canada is planning to grant her honorary citizenship. But under her country’s proposed new constitution, the jailed Ms. Suu Kyi would not be eligible to run for office because her deceased husband was not born in Burma.

The executive director of the Washington-based U.S. Campaign for Burma, Aung Din, said yesterday that he did not trust the junta’s estimated casualty numbers from the cyclone, which it raised yesterday to 10,000 from 350. The death toll could be raised to 20,000, he said. Most Burmese now will have even less access to polling stations than before the storm, and counting ballots will be more challenging, so the government “will have an easy opportunity to cheat,” he said.

“It would be very, very odd, I think, if they went ahead and held a referendum this Saturday,” Laura Bush told reporters yesterday, adding that the junta’s generals, who failed to notify residents before the storm hit, should now accept outside help.

The U.N. Security Council on Friday called on the Burmese junta to ensure that their “roadmap for democratization” be “inclusive and credible.” After weeks of haggling, council members, including Burma’s closest ally, China, agreed to adopt the American-proposed statement, but not before weakening it by dropping Ms. Suu Kyi’s name from the text.

The statement “delved into matters” that fall “within the domestic domain of my country and we find this highly objectionable,” the Burmese ambassador to the United Nations, Kyaw Tint Swe, responded in a letter to the council president. The statement passed only because of “tremendous pressure exerted by powerful members of the council on other members,” he wrote, apparently referring to America.

But as disease and hunger loom in the aftermath of the cyclone, the junta may be forced to curtail its self-imposed isolation.

“The response to this cyclone is just the most recent example of the junta’s failures to meet its people’s basic needs,” Mrs. Bush said, detailing the total devastation the generals have wrought on the country’s economy. The first lady urged the junta to accept outside help in the aftermath of the disaster, “and maybe that will be the something good that can come out of this terrible destruction,” she said.

American and U.N. officials, as well as those from several other countries, said they are ready to provide immediate assistance to the cyclone victims, but only if Burma’s government permits them full access to the areas hit by the storm, and the ability to ensure that food and medicine will be distributed to those who need it and not to people favored by the regime.

America is already spending $250,000 in Burma, and Europe has pledged $3 million. Washington, which has imposed strict economic sanctions on Burma, is ready to add more funds, Mrs. Bush said. But the government has to allow in a team that can assess the situation.

“The United Nations is very much committed to actively assisting” Burma’s people, Secretary-General Ban said yesterday, shortly before U.N. officials met with Mr. Swe, the Burmese ambassador, in an attempt to ensure access to the country.

Mrs. Bush’s interest in Burma, which she said began with learning about Ms. Suu Kyi, has been echoed by several Hollywood stars, who held a rally in support of Burma’s opposition last week. The actress Anjelica Huston plans to join the U.S. Campaign for Burma at a briefing for U.N. reporters this week.