China urges Japan to stop overstepping the line, retract its erroneous words and deeds, and honor its commitment to China with concrete actions, foreign ministry spokesperson Mao Ning said Monday.

It was reported that recently some Japanese politicians claimed that China had "overreacted" to the wrongful remarks made by Japanese Prime Minister Sanae Takaichi regarding Taiwan.

In response, Mao told a regular news briefing that China has repeatedly stated its solemn position on the wrongful remarks made by Takaichi regarding Taiwan, saying that the relevant remarks seriously violate the spirit of the four political documents between China and Japan, and cause fundamental damage to the political foundation of China-Japan relations.

Mao said that during the discussions on resuming China-Japan diplomatic ties, China explicitly put forth three principles: the Government of the People's Republic of China is the sole and legal government representing the Chinese people; the Taiwan Province is an inalienable part of the territory of the People's Republic of China; and the so-called "Taiwan-Japan Treaty" is illegal and invalid and must be abrogated.

She said in 1972, the two countries signed the Sino-Japanese Joint Statement and officially established diplomatic relations. Three places in the joint statement are related to the Taiwan question. First, in the opening paragraphs, it is written that the Japanese side "reaffirms its position that it intends to realize the normalization of relations between the two countries from the stand of fully understanding 'the three principles for resuming diplomatic relations' put forward by the Government of the People's Republic of China." Then Article 2 says that "the Government of Japan recognizes that Government of the People's Republic of China as the sole legal Government of China." And Article 3 says 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 stand of the Government of the People's Republic of China, and it firmly maintains its stand under Article 8 of the Potsdam Proclamation."

In 1978, the two countries signed the Treaty of Peace and Friendship Between China and Japan, which explicitly stated that the Sino-Japanese 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," Mao said, adding that the treaty affirmed the principles and contents of the joint statement in legal terms and set out the legal parameters for China-Japan relations.

Mao said that in 1998, the two sides released the China-Japan Joint Declaration on Building a Partnership of Friendship and Cooperation for Peace and Development, in which Japan undertook to "continue to maintain its stand on the Taiwan question which was set forth in the Sino-Japanese Joint Statement" and "reiterated its understanding that there is one China." It is stated in the document that Japan will continue to only maintain its exchanges of private and regional nature with Taiwan, which ruled out the legal possibility of Japan developing official relations with Taiwan.

In 2008, the China-Japan Joint Statement on All-round Promotion of Strategic Relationship of Mutual Benefit stipulated clearly in Article 5 that "The Japanese side reiterated that it will continue to abide by its position on the Taiwan question stated in the Sino-Japanese Joint Statement," according to Mao.

"The above is what is laid out in the four political documents between China and Japan regarding the Taiwan question. It constitutes the solemn commitment made by the Japanese government and has a legal effect under international law. There is no room whatsoever for ambiguity or misinterpretation," Mao said, adding that "whichever political party or person is in power in Japan, they must always abide by the commitment of the Japanese government on the Taiwan question."

"We urge Japan to approach history and relations with China in a responsible way, stop crossing the line and playing with fire, retract the wrongful remarks and seriously act to honor Japan's commitment to China," Mao said.