China seriously urges Japan to abide by the one-China principle and be cautious in its words and actions regarding the Taiwan question, Foreign Ministry spokeswoman Mao Ning said at a press briefing in Beijing on Monday. Mao's remarks came after she was asked to respond to a question on a reply letter issued by the Japanese government.
It was reported that recently, a Japanese Diet member submitted a letter of inquiry to the Japanese government, saying that the 1972 China-Japan Joint Statement contains the words that "The Government of the People's Republic of China reiterates that Taiwan is an inalienable part of the territory of the People's Republic of China. The Government of Japan fully understands and respects this position of the Government of the People's Republic of China". The Diet member asked whether Japanese local governments and local councilors have the legal obligation to observe this position. In response to this, the Japanese government issued a reply letter, claiming that the 1972 China-Japan Joint Statement is "not legally binding."
The reports said that successive Japanese cabinets all believe that the joint statement is "not legally binding", and the reply letter once again shows that the Joint Statement does not restrict Japanese local councilors' activities in Taiwan.
"There is but one China in the world, Taiwan is an inalienable part of China's territory, and the government of the People's Republic of China is the sole legal government representing the whole of China. China firmly opposes official interaction of any form between China's Taiwan region and countries having diplomatic ties with China. The one-China principle is the political foundation of China-Japan relations," she said.
Mao said in 1972, the Chinese and Japanese governments signed the China-Japan Joint Statement, in which the Japanese side explicitly pledged that "The Government of Japan recognizes the Government of the People's Republic of China as the sole legal Government of China. The Government of the People's Republic of China reiterates that Taiwan is an inalienable part of the territory of the People's Republic of China. The Government of Japan fully understands and respects this position of the Government of the People’s Republic of China, and it firmly maintains its position under Article 8 of the Potsdam Proclamation."
Article 8 of the Potsdam Proclamation reiterates that the "terms of the Cairo Declaration shall be carried out." And the 1943 Cairo Declaration explicitly demands that "all the territories Japan has stolen from the Chinese" to China. These documents not only confirm the fact that Taiwan belongs to China, but also constitute the legal basis for ending the state of war between the Allied Nations and Japan and building the post-war international order in the Asia-Pacific. They certainly are legally binding, said Mao.
"In 1978, China and Japan signed the Treaty of Peace and Friendship Between China and Japan, in which the two sides affirmed that the China-Japan Joint Statement 'constitutes the basis for relations of peace and friendship between the two countries and that the principles set out in that statement should be strictly observed.' The treaty was signed by the Chinese and Japanese governments, and officially came into effect after deliberation and approval by the legislators of the two countries. It affirmed the principles and contents of the joint statement in legal terms and is certainly legally binding," she said.
"Taiwan has been back under China’s sovereign jurisdiction for 80 years. The Japanese side attempted to obscure historical facts regarding the Taiwan question, which severely misleads the Japanese people, violates the Japanese government’s promise of adhering to the one-China principle, challenges the political foundation of China-Japan relations and sends a significantly wrong message to the “Taiwan independence” forces. We firmly oppose this. We seriously urge the Japanese side to abide by the principles and spirit of the four political documents with China, earnestly fulfill relevant legal obligations, act prudently on the Taiwan question and honor its promise of adhering to the one-China principle with concrete actions," she said.

China urges Japan to be cautious in words, actions regarding Taiwan question: FM spokeswoman