The unexpected visit by a senior Chinese military official to the United States is widely seen as being linked with territorial tensions in Northeast Asia, and analysts said the Diaoyu Islands issue would be discussed by the two militaries.

Cai Yingting, deputy chief of the general staff of the People's Liberation Army, takes a photo with a visiting Werner Frels, inspector general of the German Army, on March 13, 2012 in Beijing. [File photo]

Cai Yingting, deputy chief of the general staff of the People's Liberation Army, left Beijing on Monday for an official visit to the US. This is the second visit by a senior Chinese military official to the US in three months. Defense Minister Liang Guanglie paid a six-day visit to the country in May.

Neither China nor the US announced Cai's visit in advance. He is widely believed to be talking to Washington about the escalating tension between China and Japan over the islands, to which Japan also lays claim, although it is indisputable Chinese territory.

Cai's entourage includes several chiefs of Chinese military areas and Chen Shoumin, deputy head of the strategic planning department of the PLA General Staff Headquarters. This group is likely to work on more specific and transparent development plans for the two militaries. The South China Sea and the Diaoyu Islands are issues of common concern at the top of the discussion agenda, said Zhai Dequan, deputy secretary-general of the China Arms Control and Disarmament Association.

On Tuesday, Washington and Japan launched a 37-day military drill in the western Pacific Ocean. An official from the Japanese Defense Ministry indicated that the drill was devised to "take back" the Diaoyu Islands, while observers said it showed Washington's military support for its ally Tokyo over the islands.

Without the US' strategic pivot to the Asia-Pacific region, Japan would not have created so much friction over the islands, Peng Guangqian, a Beijing-based military analyst, told Xinhua News Agency.

China is likely to raise the islands issue during Cai's visit, hoping that Washington's moves in northeast Asia will not target any third party and will instead strengthen regional stability, said Lu Yin, a researcher with the Strategic Research Institute at the National Defense University of the PLA.

"But more importantly, I believe both sides will definitely discuss three chronic obstacles to ties between the two militaries: US arms sales to Taiwan, military surveillance close to China's coast and discriminatory regulations prohibiting certain military exchanges with China," she said.

"Without solving these issues, bilateral military ties can hardly be boosted further."

The development of military relations lags far behind the overall relations between the two countries, said Ni Feng, a researcher of American Studies at the Chinese Academy of Social Sciences, adding that Cai's trip could reduce mistrust between both militaries.

The PLA delegation is scheduled to visit the US army base at Fort Hood, Texas, and bases in Missouri and Hawaii, followed by the Pentagon, the Hong Kong-based Phoenix TV cited the US Department of Defense as saying on Wednesday.