Source: Ministry of Foreign Affairs website

Question: According to reports, Japanese Liberal Democratic Party Members and President of the "Japanese and Chinese Parliamentary Committee Meeting", Keiji Koya visited Taiwan from August 22 to 24 and met with Tsai Ing-wen. What is China’s comment on this?
Answer: Keiji Koya ignored China's solemn representations and insisted on visiting Taiwan, China, roughly interfering in China's internal affairs, blatantly violated the spirit of the one-China principle and the four political documents of China and Japan, and sent a serious wrong signal to the separatist forces of "Taiwan independence". China strongly condemns the above-mentioned bad behaviors and will take resolute and effective measures to defend national sovereignty and territorial integrity.
Taiwan is an integral part of China's sacred territory. The Taiwan issue concerns the political foundation of China-Japan relations and the basic trust between the two countries. Japan has made solemn commitments to China. Japan's colonial rule over Taiwan lasted for half a century and bears serious historical culprits to the Chinese people. It should be cautious in its words and actions. In order to seek political self-interest, some Japanese politicians colluded with the "Taiwan independence" forces and performed with the trend; the Japanese government allowed its political manipulation to undermine China's sovereignty and territorial integrity. This kind of betrayal and ill-intentioned behavior is doomed to end in failure and cannot stop China's historical process of achieving complete national reunification. China urges Japan to reflect deeply on history, abide by the principles of the four political documents of China and Japan and its so far promises, stop provoking troubles on the Taiwan issue, and not to wade through muddy waters in the Taiwan Strait and seek personal gain, and not to go further and further on the wrong path.