China on Thursday warned that Japan "will constitute an act of aggression" if it intervenes by force in the Taiwan Strait situation, and vowed that "China will resolutely strike back" in such a case.

The warning followed remarks last week by Japanese Prime Minister Sanae Takaichi, who hinted at the possibility of Japan's military intervention in what she called a "survival-threatening situation" for Japan.

Japan colonized Taiwan from 1895 to 1945 and has repeatedly used "survival-threatening situation" to justify wars of aggression in history. On Thursday, Takaichi once again used such language.

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Foreign Ministry spokesman Lin Jian said that despite China's solemn representations and strong protests over the remarks, Japan had so far refused to retract them. "Japan must immediately correct and retract its malicious remarks, otherwise it will bear all the consequences," Lin said at a daily news conference in Beijing.

The attempts by Japanese politicians to interfere in Taiwan Strait affairs "are not only a gross violation of international justice and a blatant provocation against the postwar international order, but also a serious disruption to China-Japan relations", he said. "We will firmly exercise the right to self-defense granted by the United Nations Charter and international law, and resolutely safeguard sovereignty and territorial integrity."

Lin urged Japan to deeply reflect on its historical crimes, immediately stop interfering in China's internal affairs, and cease its erroneous, provocative and cross-the-line words and actions.

"Do not play with fire on the Taiwan question, as those who play with fire will surely backfire," he added.

Lin emphasized that how to resolve the Taiwan question and achieve reunification is a matter for the Chinese people themselves, which brooks no interference from any external forces.

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On Wednesday, a spokesperson for the US State Department responded to Japanese media's query about Takaichi's remarks and said the US is committed to maintaining peace and stability in the Taiwan Strait and opposes any unilateral changes to the status quo by either side.

In response, Lin said Beijing wants to reiterate that the Taiwan question is "at the center of China's core interests" and "the first and foremost red line that cannot be crossed in China-US relations".

"We urge the United States to adhere to the one-China principle and the three China-US joint communiques, stop condoning or supporting the 'Taiwan independence' separatist forces, and stop damaging China-US relations as well as peace and stability in the Taiwan Strait," he said.

Contact the writers at zhangyunbi@chinadaily.com.cn