Myanmar's obstruction of international efforts to help cyclone victims cost "tens of thousands of lives," Defense Secretary Robert Gates said Saturday in his strongest condemnation to date of the military government there.

"We have reached out, frankly, to Myanmar multiple times during this crisis in very direct ways," Gates told an international audience. "It's not been us that have been deaf and dumb in response to the pleas of the international community, but the government of Myanmar. We have reached out, they have kept their hands in their pockets."

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With U.S., British and French Navy ships off the coast of Myanmar poised to leave because they have been blocked from delivering assistance to the ravaged country, Gates said the U.S. will not forcefully bring in supplies without permission of the government, and will continue to "respect the sovereignty" of Myanmar.

The growing displeasure with the Myanmar government has permeated this week's conference on international security, coming up in nearly all conversations between leaders from around the world. Military officials have indicated that they are about to withdraw the U.S. Navy ships within days, since it does not appear that the Myanmar government will change its mind and allow the vessels to unload their supplies.

Gates said the U.S. has provided aid to other countries while respecting their independence. But with Myanmar, he said, "the situation has been very different — at a cost of tens of thousands of lives. Many other countries besides the United States also have felt hindered in their efforts."

The Pentagon chief also rejected one conference questioner's suggestion that America is using sanctions and isolating Myanmar, similar to failed U.S. policies against Cuba. And he insisted that efforts to provide aid will continue.

In a wide-ranging speech, Gates looked ahead to the next White House administration, saying the new U.S. president will inherit the worrisome issue of North Korea's nuclear ambitions but will continue America's enduring commitment to Asia.

While he said he could not make specific policy predictions for the next administration, Gates told the annual Shangri-la conference that there will be "no change in our drive to temper North Korea's ambitions, a policy not possible without China's valued cooperation."

Despite the often divergent views of the Republican and Democratic candidates, Gates said he is confident that the strong U.S. ties to Asia will continue "no matter which political party occupies the White House next year."

"Any speculation in the region about the United States losing interest in Asia strikes me as either preposterous, or disingenuous, or both," he said.

The reference to China was one of several in a speech that sounded two distinct tones on the communist giant — at times extending a friendly hand and at others offering a subtle but somber warning.

Gates first noted that relations with China have improved, and that leaders have begun a series of discussions on issues to "help us understand one another better, and to avoid possible misunderstanding."

A long-sought direct telephone link between the U.S. and China has finally been established, and Gates said he used it recently to speak with the defense minister.

On the other hand, Gates took unmistakable jabs at China without mentioning its name, calling, for example, for greater openness about military modernization in Asia.

In recent annual reports the Pentagon has criticized China for its massive military buildup, saying its motives and spending are unclear.

"We desire to work with every country in Asia to deepen our understanding of their military and defense finances, and to do so on a reciprocal basis," Gates said.

Lack of such clarity, Gates said, can lead to outright suspicion.

In response, the top ranking Chinese official at the forum took aim at U.S. missile defense policies — which include plans for anti-missile defenses with Japan, as well as the deployment of missile defense sites in Poland and the Czech Republic.

Lt. Gen. Ma Xiaotian, deputy chief of the General Staff for the People's Liberation Army, said developing such an offensive — rather than purely defensive — system could tip the balance of power and threaten peace.

"We do not support either side to take the initiative to break the balance," he said. He also said dismissed claims that China's military is dramatically expanding. China's spending on defense, he said, is low.

Gates has consistently sounded a more conciliatory tone toward China, which he visited late last year for high-level meetings with the country's leaders. However, relations have been strained by revelations in March that the U.S. military mistakenly delivered fuses for long-range missiles to Taiwan, triggering a strong protest from Beijing.

On Friday, Gates declined to discuss the lengthy report he received Tuesday on the blunder and, more broadly, on the Pentagon's handling of nuclear-related materials.

Gates, who has made four major trips to Asia during his 17-month tenure as Pentagon chief, has also suggested that the U.S. — as a Pacific nation — has been a key factor in the ability of other Asian countries to grow and prosper.

In another veiled reference to China, he said the U.S. presence in the region has opened doors and protected "common spaces on the high seas, in space and, more and more, in the cyber world."

U.S. officials have suspected the Chinese of trying to hack into U.S. government computers. In one instance, a number of Pentagon computers had to be taken off line for several days — but officials never openly blamed China.

Gates was scheduled to leave Singapore on Sunday and then visit defense leaders in Thailand and South Korea.