China's Foreign Minister Yang Jiechi sparked angry exchanges with Japanese diplomats at the United Nations by accusing Japan of stealing disputed islands.
Chinese and Japanese envoys staged a series of attacks during Thursday's session after Yang heightened tensions over the East China Sea islands and reopened old diplomatic wounds over World War II.
The Japanese government's purchase of the uninhabited islands from a private owner this month has infuriated Beijing and set off violent protests in several Chinese cities.
"China strongly urges Japan to immediately stop all activities that violate China's territorial sovereignty, take concrete actions to correct its mistakes and return to the track of resolving the dispute through negotiation," Yang told the UN assembly.
China has demanded the return of the uninhabited islands, known as the Diaoyus in Chinese and the Senkakus in Japanese, for decades. Taiwan also claims the islands.
Yang reaffirmed his country's historical claim that Japan tricked China into signing a treaty ceding the islands in 1895. Japan states that the islands were legally incorporated into its territory.
"The moves taken by Japan are totally illegal and invalid. They can in no way change the historical fact that Japan stole Diaoyu and its affiliated islands from China and the fact that China has territorial sovereignty over them," said the Chinese minister.
Japan's move was in "outright denial" of its defeat in World War II, he added, reaffirming China's repeated references to the 1939-45 war.
In Tokyo Japan's Chief Cabinet Secretary, Osamu Fujimura, told reporters Yang's remarks were "totally groundless".
"It is important for the two countries to calmly act with each other from a broad perspective, while fostering and maintaining communication," he said.
Yang and Japan's Foreign Minister Koichiro Gemba held stern talks on the dispute in New York on Tuesday, and Yang's speech sparked sharp exchanges between Japanese and Chinese diplomats as each sought a right of reply.
Insisting that Japan legally incorporated the islands into its territory in 1895, Japan's deputy UN ambassador Kazuo Kodama said that "an assertion that Japan took the islands from China cannot logically stand."
Kodama added that the references to World War II were "unconvincing and unproductive".
China's UN envoy Li Baodong responded that "the Japanese delegate once again brazenly distorted history, resorting to spurious fallacious arguments that defy all reason and logic to justify their aggression of Chinese territory."
"The Japanese government still clings to its obsolete colonial mindset," Li added. "China is capable of safeguarding the integrity of its territory," the ambassador warned.
When Kodama responded that the islands "are clearly an inherent territory of Japan", Li returned to the attack. He said his Japanese counterpart "feels no guilt for Japan's history of aggression and colonialism."
The Japanese government's purchase of the islands is based purely on "the logic of robbers", he stormed.