British aircraft carrier the Queen Elizabeth made its first port call in Japan on Saturday, aiming to showcase the two countries' defense cooperation in the Indo-Pacific region where China's military has been growing increasingly assertive.

Taking part in a joint exercise since Thursday with Japan, the United States, the Netherlands and Canada, the flagship of Britain's Carrier Strike Group arrived at the U.S. Navy base in Yokosuka, southwest of Tokyo, and is scheduled to depart next Thursday.

Photo taken from Kyodo News helicopter shows British aircraft carrier the Queen Elizabeth sailing in Tokyo Bay on Sept. 4, 2021, before arriving at the U.S. Navy base in Yokosuka, southwest of Tokyo, to make its first port call in Japan. (Kyodo)

The exercise is aimed at strengthening the participating countries' cooperation toward realizing the "free and open Indo-Pacific" initiative led by Tokyo and Washington in a veiled counter to Beijing which is locked in territorial disputes in the East and South China seas with neighboring countries.

Commodore Steve Moorhouse, commander of the Carrier Strike Group, said in a Twitter video message that the visit is part of Britain's commitment to strengthen its "diplomatic, economic and security ties in the Indo-Pacific" area, vowing to take the bilateral relationship with Japan "to a whole new level."

"The Carrier Strike Group's presence embodies the United Kingdom's support for the freedom and security of the region's vital trading routes, and for an international system that benefits all countries," Moorhouse said.

During the port call, the around 1,240 crew members will not disembark from the warship, according to the Yokosuka city office. The strike group departed Britain in May.

Commissioned in 2017 with state-of-the-art weaponry, the Queen Elizabeth is Britain's largest aircraft carrier capable of carrying up to 40 aircraft, according to the Royal Navy.

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