US Secretary of Defense Leon Panetta left Qingdao on the afternoon of Sept 20, concluding his first trip to China as Pentagon chief.

After arriving in the coastal city in east China from Beijing that morning, Panetta visited the headquarters of China's North Sea Fleet and toured Chinese naval vessels.

Panetta said he was impressed by the arrangements of the Chinese, and called for more exchange and cooperation between the two navies to increase mutual trust and understanding.

Panetta arrived in Beijing on the evening of Sept 17 after a two-day trip to Japan. His week-long Asia trip, including a following stop in New Zealand, is his third one in 11 months.