China's leader-in-waiting Xi Jinping has met with U.S. Defense Secretary Leon Panetta, in the first public meeting with a visiting foreign dignitary since his mysterious disappearance from public life.

Xi appeared healthy and relaxed as he shook hands with Panetta and posed for photographs in the Great Hall of the People in Beijing Wednesday.

The 59-year-old had not been seen in public for two weeks before re-emerging Saturday. The unexplained absence, which came just weeks before a sensitive political transition, led to speculation about Xi's health.

On Wednesday, a smiling and energetic Xi said he hoped Panetta's visit will help advance “state-to-state and military-to-military” ties between Washington and Beijing.

Panetta, who is on a week-long tour of Asia, told Xi he looked forward to promoting security ties and improving dialogue between the two “great Pacific nations.”

During Tuesday meetings with his Chinese counterpart, Panetta said greater military ties are key to avoiding confrontation between Washington and Beijing, who have grown suspicious of each other's expanding roles in the Asia-Pacific.

The Pentagon chief's visit comes as China and Japan, an American ally, are involved in a bitter territorial dispute about a group of islands in the East China Sea. Panetta urged both sides to exercise restraint and repeated Washington's insistence that it does not take sides in the dispute.

But an article in the Communist Party-controlled Global Times on Wednesday says it is “obvious” that Washington is partial to Japan. The newspaper, which often reflects official thinking, says Beijing should use Panetta's visit to let the United States know it will take all necessary steps to safeguard the islands, known in Chinese as Diaoyu and in Japanese as Senkaku.

Boisterous anti-Japan protests that spread across China on Tuesday were also partly focused on the United States. The U.S. State Department issued a statement that a car carrying U.S. Ambassador to China Gary Locke was mildly damaged after about 50 protesters surrounded it outside the U.S. embassy in Beijing. The statement says the ambassador was not hurt and the protesters were dispersed by Chinese security personnel.