China told Japan on Tuesday it "must abandon any illusion" it has over a territorial dispute as the two sides held high-level talks over rival claims to East China Sea islands.
Vice foreign minister Zhang Zhijun said China "will absolutely not tolerate any unilateral action taken by the Japanese side that infringes on China's territorial sovereignty", according to a ministry statement.
"The Japanese side must abandon any illusion, face up to its erroneous actions and correct them with credible steps," said the statement, released by China after the talks which were attended by Zhang and the Japanese vice foreign minister Chikao Kawai.
The discussions in Beijing were held after a long-running dispute over the Diaoyu islands - known as Senkaku in Japan - flared up, leading to street protests across China.
A number of Japanese companies, including Panasonic and Honda, were forced to temporarily halt production last week, as owners feared for the safety of their staff and property.
China's foreign ministry described the talks as "candid" and said the two sides agreed to keep discussing the issue.