China on Friday expressed grave concerns over a joint statement released by the US and Japan, urging the two countries to discard their Cold War mind-set.

"It will be detrimental to the proper solution of relevant issues and the stability of the region to make indiscreet criticisms or remarks on the affairs of other countries," said Chinese foreign ministry spokesperson Qin Gang.

The joint statement came on Friday, a day after US President Barack Obama and Japanese Prime Minister Shinzo Abe held talks in Tokyo.

The joint statement said the disputed Diaoyu Islands between Japan and China fall under the scope of the US-Japan Treaty of Mutual Cooperation and Security, adding that the US and Japan "share strong concern over" China's declaration of an Air Defense Identification Zone (ADIZ) in the East China Sea.

The US-Japan security treaty cannot change the fact that the Diaoyu Islands are China's inherent territory, Qin said.

Xinhua