China reacted strongly Friday after Japan said it could use its Self-Defense Forces in the territorial dispute over the Senkaku Islands in the East China Sea also known as Diaoyu Islands in Chinese.

Chinese Foreign Ministry spokesman Hong Lei told a news conference on Friday that there was no change in China’s stance towards protecting its territory. He also expressed Beijing’s deep concern and displeasure over what it called Japan’s irresponsible remarks.

He also said China would watch whether Japan would solve the issue in a diplomatic manner, urging Tokyo to make sincere efforts.

The Chinese reaction comes after Japanese Prime Minister Yoshihiko Noda said in parliament Thursday that Japan would take firm action, including deploying Self-Defense Forces, in the case of surrounding countries engaging in illegal behavior in Japanese territory.