BEIJING >> The Chinese military said Thursday that while the security situation in Asia and the Pacific was generally stable, it was becoming “more intricate and volatile,” with no clear solutions for tension points like the divided Korean Peninsula and with the United States increasing its involvement in regional issues.

The military’s vision was laid out in a national defense white paper, a document published every two years since 1998. The paper tried to walk a line between trumpeting the modernization efforts of the Chinese military and assuaging the fears of foreign governments and analysts that the fast-growing People’s Liberation Army would be used for expansionist purposes or regional dominance.

It stressed that China’s military buildup was purely defensive, a position Chinese leaders have long taken. The paper had more detail than previous editions on China’s efforts to establish confidence-building measures with foreign militaries. In the past year, perceptions by foreign countries of China’s military growth and of a more assertive foreign policy have resulted in diplomatic discord and discomfort, particularly between China and the U.S.

“China attaches importance to its military relationship with the United States and has made ongoing efforts towards building a sound military relationship,” Senior Col. Geng Yansheng said at a news conference Thursday, reading from a text. “The Chinese military is now taking steps to advance exchanges with the U.S. military this year.”

But “there’s no denying that in developing military relations, we still face difficulties and challenges,” Geng added.

The white paper observed that in the Asia-Pacific region, “relevant major powers are increasing their strategic investment.”

“The United States is reinforcing its regional military alliances, and increasing its involvement in regional security affairs,” it added.

Geng said that the army’s chief of general staff, Gen. Chen Bingde, would visit the U.S. in May. Robert Gates, the U.S. defense secretary, flew to Beijing in January to smooth over military-to-military relations that had been frozen after the Obama administration announced arms sales to Taiwan in January 2010. In June, Gates got into a prickly dispute with Gen. Ma Xiaotian at a security meeting in Singapore, an episode that revealed the deep fissures in the military relationship.

Gates had to navigate yet another tricky diplomatic situation here when the Chinese military tested a J-20 stealth fighter jet in Sichuan province while he met in the Chinese capital with President Hu Jintao.

In December, Adm. Robert F. Willard, the commander of U.S. Pacific Command, told a Japanese newspaper that China had a working design for an anti-ship ballistic missile that could strike aircraft carriers and could soon be ready for deployment. The missile, known as a “carrier killer,” has become a symbol in Western military circles of the Chinese army’s technological advances.

The weapon “is not science fiction,” Andrew Erickson, a professor at the U.S. Naval War College, said in an email interview earlier this year. “It is not a ‘smoke and mirrors’ bluff,” he wrote. “It is not an aspirational capability that the U.S. can ignore until some point in the future.”

Of equal or greater import is China’s plan to soon deploy an aircraft carrier known to be under construction. But the white paper, while ostensibly aimed at making China’s military development more transparent, did not discuss the carrier project. Geng dodged a question about it at the news conference.

The paper noted that China still faced challenges from “separatists” striving for the independence of the restive western regions of Tibet and Xinjiang and the self-governing island of Taiwan.

“Pressure builds up in preserving China’s territorial integrity and maritime rights and interests,” it said. “Nontraditional security concerns, such as existing terrorism threats, energy, resources, finance, information and natural disasters, are on the rise. Suspicion about China, interference and countering moves against China from the outside are on the increase.”

The Chinese government has announced that the military budget for 2011 is about $92 billion, up 12.7 percent from 2010. The previous announced annual increase was 7.5 percent, the first time in years that the reported growth had dipped below double digits.

“China pursues a national defense policy which is defensive in nature,” the white paper said. “China will never seek hegemony, nor will it adopt the approach of military expansion now or in the future, no matter how its economy develops.”

© 2011 The New York Times Company