China on Wednesday asked Japanese Prime Minister Sanae Takaichi to retract "wrongful remarks" on Taiwan, warning that failing to do so would result in "countermeasures".
The warning comes a day after officials from the two countries, who held talks in Beijing to tone down tensions, failed to resolve their differences.
Chinese Foreign Ministry spokesperson Mao Ning told a media briefing here that Takaichi recently made erroneous remarks concerning Taiwan, grossly interfered in China's internal affairs, trampled on international law, challenged the post-war international order and triggered the outrage of the Chinese people.
"We urge Japan to retract the wrongful remarks and stop stirring up troubles, and take concrete steps to preserve the foundation of the bilateral relations," she said.
"If Japan refuses to retract those remarks, China will have no choice but to take serious countermeasures, and all the consequences will be borne by the Japanese side," Mao said.
Answering a question, Mao also said that Japan is "totally unqualified" to seek a permanent seat on the UN Security Council, asserting that certain countries incapable of taking up the responsibility to maintain international peace and security are unqualified to become members of the Security Council.
The two countries clashed in the United Nations on Tuesday over the issue.
Japan, along with India, Germany and Brazil, is staking a claim for permanent membership of the UN Security Council, which is opposed by China.
The flare-up in their bilateral ties occurred after Takaichi, regarded as a China hawk, told a parliamentary committee on Nov. 7, that a Chinese military attack on Taiwan could be a "survival-threatening situation" for Japan, which could exercise its right to collective self-defence.
China, which considers Taiwan as part of its mainland, maintains that the Taiwan issue is purely an "internal affair."
Speaking at the UNGA on Tuesday, China's Permanent Representative Fu Cong said Takaichi's claim that the "Taiwan contingency" could be a "survival-threatening situation" for Japan.
It implied that Japan may invoke the so-called right to collective self-defence to interfere militarily in the Taiwan Strait, state-run Xinhua news agency reported.
Besides lodging diplomatic protests, China has asked its citizens to avoid travelling to Japan, which resulted in a spate of cancellations of Chinese tourists. China is the largest source of tourists to Japan with about 7.4 million trips this year.
It also stopped the recently resumed imports of aquatic products from Japan and stepped up its coast guard ship patrols in the disputed waters in the East China Sea.