Washington should "be cautious in words and actions in regard to the Diaoyu Islands", the Ministry of National Defense said on Friday in a stern rebuke to recent remarks by a top US navy official.

Admiral Harry Harris, commander of the US Pacific Command, addressed the Chinese territory in the East China Sea on Wednesday at a Washington think tank event by saying that "we will clearly defend them if they are attacked by China", Japan's Kyodo news agency reported.

In a written reply to China Daily on Friday, the Chinese ministry said: "China has taken notice of the relevant report."

"The Diaoyu Islands and affiliated islets are China's inherent territory, and China's sovereignty over them is beyond dispute. The Chinese military firmly safeguards national sovereignty and security, and its determination to safeguard regional peace and stability is unswerving," the ministry said.

The US should "take tangible efforts in safeguarding the peace and stability in the region as well as the big picture of China-US relations", the ministry added.