U.S. Secretary of Defense Leon Panetta left the east China city of Qingdao Thursday afternoon, concluding his first trip to China as the Pentagon chief.

After arriving in Qingdao from Beijing Thursday morning, Panetta visited the Headquarters of China's North Sea Fleet, and toured Chinese naval vessels.

He said during the visit that he was impressed by the arrangements of the Chinese, calling for more exchange and cooperation between the two navies in a bid to increase mutual trust and understanding.

Panetta is in the Asia-Pacific region for a week-long trip. He completed a two-day visit to Japan on Monday and will now go to New Zealand.