BEIJING – As they prepare to join forces for their largest military exercise in modern history, China and Russia have billed this week’s maneuvers as a cooperative fight against terrorism. But they’re also sending a message to Washington, analysts say: Don’t push the two former Cold War adversaries too far.

The eight-day exercise, which will begin today, will be the most extensive since Beijing and Moscow fought together against American-led forces during the Korean War half a century ago. Originally billed as a modest exercise when proposed last year, it has grown in scope to include nearly 10,000 troops using a range of sophisticated weapons systems.

“I can’t help but think it’s intended as a bit of a poke in the eye at the U.S., a way of [China] saying, ‘We do have good relations with Russia,'” a retired American admiral and the Asia-Pacific director at the Institute for Foreign Policy Analysis in Washington, Eric McVadon, said.

Moscow and Beijing said in their respective announcements earlier this month that their Peace Mission 2005 exercise will kick off in the Russian Far East port of Vladivostok but will take place largely in and around China’s Shandong peninsula and is aimed at countering terrorism, extremism, and separatism.

“Part of the exercise is beach landing and sea-air deployment, which has nothing to do with fighting terrorism,” a military expert teaching at Shanghai Normal University, Ni Lexiong, said. “Generally, it’s being held because of the long-term U.S. aggressive military stance toward China and Russia.”

Even as the Bush administration expresses growing concern about China’s military buildup, Beijing and Moscow have bridled at America’s recent moves in their backyard.

They include announced troop redeployments in South Korea and Japan designed to create a leaner, more responsive force as well as the redeployment of long-range bombers and nuclear attack submarines to Guam, part of a stated goal of bolstering the American presence in the Asia-Pacific region.

Also worrisome, particularly for Moscow, has been America’s expanding military presence in oil-rich Central Asia, part of Russia’s traditional sphere of influence. The former Soviet states of Georgia, Ukraine, and Kyrgyzstan have seen the toppling of their autocratic, Russian-leaning governments over the last 18 months, replaced by elected regimes that lean toward the West.

Beijing also has bristled at criticism of its military buildup from American conservatives, including a high-profile June speech by Defense Secretary Rumsfeld in Singapore and the July 19 release of a critical Pentagon report calling China a potential long-term threat.

“I’m not sure Russia and China are trying to deter the U.S. outright,” the secretary-general of Taiwan’s Chinese Council of Advanced Policy Studies in Taiwan, Andrew Yang, said. “But they see this [region] as their territory, and they’re trying to counterbalance the U.S. position by taking a more proactive stance.”

In a thinly veiled jab at America’s sole superpower status, Russian President, Putin and Chinese President Hu Jintao denounced the “aspiration for monopoly and domination in international affairs” in a joint declaration during a Moscow summit last month.

Analysts see limits to the Chinese-Russian relationship, however, with some characterizing the current exercise as a marriage of convenience. Even as ties increase, Moscow is thought to be wary of China’s growing economic and political clout and fearful that the sparsely populated Russian Far East could become a de facto Chinese colony.

Although it has provided an abundance of arms to China, Russia has balked at selling Beijing its most advanced military hardware – and items it does sell may come with strings attached. Some Chinese Web sites suggest that Moscow sold Beijing SU-27 fighters on the condition that they remain south of the Yangtze River, a sizable distance from the Russian border.

The exercise will involve 1,800 Russian troops and nearly 8,000 of their Chinese counterparts as well as Russian anti-submarine vessels, a large landing ship, a destroyer, and 17 long-distance military transport and fighter jets.

Analysts say the exercise’s location reflects insecurity in both capitals over the breakup or further dissolution of their empires. Russia reportedly wanted the exercise staged in Central Asia, while Beijing wanted it just off Taiwan, which it considers a renegade province. The area around the Shandong peninsula was reportedly a compromise to avoid a strong Washington response over Taiwan.

Russia and China may see an opportunity to reduce the American footprint in Central Asia. In late July, Uzbekistan, miffed at American calls for an international investigation of a deadly government crackdown on demonstrators in the town of Andijan, gave America six months to vacate a southern air base that Washington has used for its Afghan campaign since late 2001.

Mr. Rumsfeld has persuaded neighboring Kyrgyzstan that an American air base there be available to pick up the slack, but the decision by Uzbekistan is still seen as an American setback. Russia and China supported the forced exit behind the scenes.

Even inside China, however, some analysts are quietly questioning Beijing’s judgment in hosting such an ambitious exercise when its relations with Washington already are strained by a huge American trade deficit, security tensions, and the recent aborted bid by state-controlled CNOOC to take over the American oil company Unocal Corporation.

“My sense is there was criticism internally about China’s decision to go ahead with it,”a senior analyst with the Center for Strategic and International Studies in Washington, Bonnie Glaser, said. “The concern is that you’re likely to [anger] America even more and you wouldn’t get anything more for it.”

But a professor of international relations at Beijing’s Qinghua University, Chu Shulong, countered that China often finds itself in something of a no-win situation. “No matter what China does with Russia, or its own military buildup, the Pentagon and Mr. Donald Rumsfeld will still regard China as a threat.”