China's position regarding the East China Sea issue remained consistent and unequivocal, Foreign Ministry spokesman Qin Gang said on Tuesday.

Qin said, "China and Japan have reached a principled common understanding on the East China Sea issue. China upholds and maintains the common understanding. This position has never changed."

Qin added that China hoped Japan could provide a more favorable environment to put the common understanding into practice.

He made the remarks in response to a question that Japan would appeal to an international maritime court if China started using an East China Sea oil and gas field for gas production.

According to the principled common understanding, the Japanese side could participate in the cooperative development of the Chunxiao oil and gas field in accordance with relevant laws of China, but the cooperative development is different from "joint development."