Japan reported that two Chinese aircraft carriers were seen operating in the Pacific Ocean for the first time, indicating an expansion of Beijing's military activities, according to the country's defense minister on Tuesday.

China's Shandong and Liaoning carriers, currently the only two in operation with a third undergoing sea trials, were both observed with their fleets in recent days, Tokyo confirmed.

A defense ministry spokesman stated, "We believe the Chinese military's purpose is to improve its operational capability and ability to conduct operations in distant areas."

Defense Minister Gen Nakatani highlighted that these sightings demonstrate the expansion of the Chinese military's activity area.

Japan has communicated through diplomatic channels to Beijing that Chinese activities should not pose a threat to Japan's safety, Nakatani added.

The Japanese military will continue to closely monitor and patrol the operations of Chinese naval warships in the region.

China's use of naval and air assets to assert its territorial claims has raised concerns among the United States and its allies in the Asia-Pacific region.

Chinese foreign ministry spokesman Lin Jian, when questioned about these movements, reiterated that the activities of Chinese warships in the relevant sea areas comply with international law and practice. He urged Japan to view the situation objectively and rationally.