U.S. Defense Secretary Leon Panetta expressed concern on Monday about mounting tensions between Beijing and Tokyo over a disputed island group, urging "calm and restraint on all sides" as anti-Japanese protests flared in China for another day.
"It is in everybody's interest - it is in everybody's interest - for Japan and China to maintain good relations and to find a way to avoid further escalation," Panetta told a news conference after meetings with the Japanese foreign and defense ministers.
The U.S. defense secretary, who arrived in China late on Monday, will meet with Chinese Defense Minister Liang Guanglie and Vice President Xi Jinping, who is due to take over as president next spring.
Panetta's visit is aimed at developing a closer military relationship with China while also working to deepen U.S. defense ties with its longtime treaty allies as part of a shift in U.S. strategic focus to the Asia-Pacific region.
As part of that effort, Panetta and Japanese Defense Minister Satoshi Morimoto announced on Monday the two countries have agreed to locate a second missile defense radar system on Japanese territory to protect against a growing North Korean ballistic missile threat.
"(The radar) will enhance the alliance's ability to defend Japan, our forward deployed forces and the U.S. homeland from a ballistic missile threat posed by North Korea," Panetta said.
An X-band missile defense radar is already in place at the Shariki base in Japan, and many U.S. warships are equipped with the radar as part of the Aegis weapons system. But the two countries agreed to begin evaluating sites for a second land-based system.
"More is better," a U.S. defense official, speaking on condition of anonymity, said in explaining the decision.
"This deployment will be a force multiplier for the United States and our allies," the official added, saying it would enable the United States to spread out its ships to better track the missile threat.
The official insisted the system was not aimed at China, but rather was "focused on addressing the growing North Korean missile threat" to the United States and its allies.
The missile defense issue illustrates the balancing act Panetta faces during his visit to the Asia-Pacific region.
He is working to build up the military capabilities of U.S. allies as part of the U.S. strategic shift while trying to reassure Beijing that Washington does not aim to thwart China's emergence as a global power.
On the islands dispute, Panetta said Washington stood by its mutual defense obligations under the U.S.-Japan security treaty, but he also pressed for Japan and China to take constructive steps to resolve the dispute peacefully.
China and Japan both claim the islands, called Senkaku by Tokyo and Diaoyu by China, which are located in waters thought to be rich in natural gas.
The protests across China were triggered by a Japanese government decision last week to purchase the islands from a private Japanese owner. Beijing warned that the Japanese move was a provocative violation of its sovereignty.
"Obviously we're concerned by the demonstrations (in China) and we're concerned by the conflict that is taking place over the Senkaku islands, and the message that I have tried to convey is a message that we have to urge calm and restraint on all sides," Panetta told reporters.