Defense Secretary Robert Gates of the United States said Sunday that Myanmar was guilty of "criminal neglect" for blocking large-scale international aid to cyclone victims and that more Burmese civilians would perish unless the military regime reversed its policy.

But despite the rising anger and frustration with Myanmar's military leaders, Gates said that defense ministers meeting in Singapore over the weekend had unanimously opposed any plan to violate Burmese sovereignty and forcibly provide relief supplies.

As a result, he said, it was probably "a matter of days" before the Pentagon withdrew four navy ships carrying supplies that have been "steaming in circles" for days in the waters off Myanmar's coast, waiting in vain for permission to ferry their cargo to storm-stricken areas.

"It's becoming pretty clear that the regime there is not going to let us help," Gates, in the strongest remarks to date by a high-ranking U.S. official, said in Singapore before heading to Bangkok on the third leg of a weeklong trip to Asia. "I'd say that unless the regime changes its approach, changes its policy, more people will die."

Admiral Mike Mullen, chairman of the Joint Chiefs of Staff, who joined Gates to answer questions, said that the government of Myanmar had given permission for 95 U.S. C-130 cargo planes to land in Yangon, the country's main city, but that much more could be brought in from the navy vessels. The relief flights have ferried in more than about 680,000 kilograms, or 1.5 million pounds, of supplies, mostly food, water, mosquito netting and plastic sheeting for shelters.