China firmly opposes Japan's adoption of a so-called name-changing bill concerning the Diaoyu Islands, and has lodged stern representations with Japan through diplomatic channels, a Chinese foreign ministry spokesperson said Monday.

Spokesman Zhao Lijian made the remarks at a routine news briefing that the Diaoyu Islands are China's inherent territory, and China is determined and resolved in safeguarding its territorial sovereignty.

"Japan's adoption of the so-called name-changing bill is serious provocation against China's territorial sovereignty. It is illegal, null and void, and cannot change the fact whatsoever that the Diaoyu Islands belong to China," Zhao said.

Zhao said that China has lodged stern representations with Japan through diplomatic channels and reserves the right to make further responses.