China said the US-Japan Security Treaty, a product of the Cold War era, should not be used to endorse Japan's claim over the Diaoyu Islands which harms China's sovereignty and rights, Foreign Ministry spokeswoman Hua Chunying told reporters at a regular press conference on Friday.

Hua made the remarks in response to the joint statement made by the US and Japan during the Security Consultative Committee, or "2+2 meeting", which said the Treaty of Mutual Cooperation and Security between the United States and Japan covers the Diaoyu Islands and also expressed what it called a "grave concern" over situation in the South China Sea.

The spokeswoman said China takes a consistent and clear stance on the Diaoyu Islands and the South China Sea issue, as its determination and will to safeguard the territorial integrity are firm.

"The US and Japan should mind their words and deeds as they are not related parties on the South China Sea issue," Hua said, urging the two countries to stop making wrong remarks and do more for regional peace and stability.