KUALA LUMPUR, Malaysia — On every stop of his Asian journey in the past week, President Obama has spoken to two audiences: America’s allies and China. The balancing act has become even trickier because of the sharp deterioration in America’s relations with Russia.

Perhaps no country has more to gain from a new Cold War than China, which has historically benefited from periods of conflict between the United States and Russia and, analysts say, could exploit these latest tensions to lean even harder on its neighbors in the region.

As Mr. Obama has traveled from Japan to South Korea and, now, Malaysia, he has delivered a carefully calibrated message to reassure America’s friends of its support while discouraging the Chinese from any thoughts of opening a second front on the Pacific Rim.

In Tokyo on Thursday, Mr. Obama vowed to defend Japan in a territorial dispute with China, but urged the Japanese to show restraint and insisted that he wanted solid relations with Beijing. The next day in Seoul, the South Korean capital, he pledged to defend South Korea from the renegade North, a Chinese ally, but went out of his way to enlist Beijing in that effort.

“We’re not interested in containing China,” Mr. Obama said, even as he embarked on what some experts said could be portrayed as a “containment tour,” visiting four countries that worry about Chinese expansionism while skipping Beijing itself.

“We’re interested in China’s peaceful rise and it being a responsible and powerful proponent of the rule of law,” Mr. Obama insisted. But he added, “In that role, it has to abide by certain norms.”

The president laid out a vivid case for why China should not mimic Russia’s adventurism. The escalating sanctions against Russia for its threats to Ukraine, he said, will weaken an economy already challenged by its reliance on oil and gas.

The portrait Mr. Obama painted of Russia was withering. Speaking in Tokyo, he said Russia “needs to diversify its economy, because the rest of the world is moving further and further off the fossil fuels that are the primary way that Russia is able to bankroll itself.”

By playing up Russia’s weaknesses and predicting that they will worsen because of President Vladimir V. Putin’s aggression, Mr. Obama seemed to be saying to Chinese officials who might be contemplating closer ties with Moscow: Stick with a winning team.

“The message is: ‘Don’t think that what Putin is doing in eastern Ukraine is so brilliant that you should be inspired by it. Don’t think that this is a model that could work for you,’ ” said Jeffrey A. Bader, who was the senior China adviser on the National Security Council until 2011.

Mr. Bader warned last week that a few poorly chosen phrases could turn Mr. Obama’s trip into a containment tour. But he said the president had gotten the balance right in Japan and South Korea, robustly reaffirming America’s support for its treaty allies while avoiding statements that would isolate or antagonize China.

So far, China’s reaction has been muted. The Chinese Ministry of Foreign Affairs issued a perfunctory objection to Mr. Obama’s assertion that the American security treaty with Japan obligates the United States to protect a clump of islands in the East China Sea that are administered by Japan but claimed by both Japan and China.

But it has been silent since then, much as it abstained from the debates in the United Nations over Russia’s actions in Crimea. China, some analysts said, is content not to pick a fight with the United States at a time when events, in Asia and elsewhere, seem to be going in its favor.

Leaders in Japan and South Korea said they were reassured by Mr. Obama’s words. But among experts in both countries, there was lingering uneasiness about the depth of American resolve.

“The wording of his statements was O.K., but if you look at his demeanor and tone, he was very nuanced and trying not to get entangled in disputes with China,” said Narushige Michishita, an expert on security policy at the National Graduate Institute for Policy Studies in Tokyo.

Lee Geun, a professor of international studies at Seoul National University, said the situation in Ukraine raised inevitable questions. “What if North Korea tries something, or what if China tries to do something with North Korea?” he said. “Would the U.S. come to South Korea’s defense?”

Administration officials say the United States is better placed in Asia than it has been for years. Malaysia, which once had an openly anti-American government, is now cautiously looking to work with the United States. Myanmar, after decades of isolation during which it became heavily dependent on China, is also eager to engage.

But none of this will spare Mr. Obama from his balancing act. In Malaysia, where he arrived on Saturday, he will meet with government officials who have come under fierce criticism from the Chinese authorities for their handling of the search for the missing Malaysian airliner. Many of the passengers on the plane were Chinese.

Malaysia has its own territorial disputes with China, in the South China Sea, on which it would welcome American support. Benjamin J. Rhodes, a deputy national security adviser, said Mr. Obama’s position was that “big nations should not be able to coerce smaller nations.”

That issue will be even more pointed in the Philippines, where Mr. Obama will travel on Monday. The country has been locked in an increasingly tense standoff with China over the Scarborough Shoal, a popular fishing ground now occupied by Chinese ships.

The United States hopes to announce an agreement to expand access for American warships and planes to bases in the Philippines, giving the United States a visible military presence there for the first time since it relinquished the Subic Bay Naval Base in 1992.

That would also send an unmistakable message to China, though last-minute legal issues in the Philippines have raised questions about whether the deal will be ready for the president to sign.

As Mr. Obama traveled from South Korea to Malaysia, even his route attested to the perils of the new Asia: Air Force One flew through an air defense zone over the East China Sea that China announced last year toreinforce its territorial claims, provoking protests from Japan.

At the time, the United States brushed aside China’s requirement that planes identify themselves when flying into the zone, dispatching two B-52 bombers to prove its point. On Saturday, an administration official said, Air Force One filed only a routine flight plan. Except for a little turbulence, the plane passed through the area smoothly.