China urged Japan on Thursday to immediately cease action concerning the Diaoyu Islands issue, noting that the actions, aimed to strengthen control over the islands, are infringement to China's territorial sovereignty.

The Diaoyu Islands and adjacent islets have been Chinese territories since ancient times, Chinese Foreign Ministry spokeswoman Jiang Yu said in response to a question at a routine press conference. She noted that China holds indisputable sovereignty over the islands.

"Any actions from Japan to strengthen the actual control over the islands are infringement to China's territorial sovereignty, which is illegal and invalid, and should be stopped immediately," Jiang said.

According to Japanese media reports, the Japanese coastguard has stationed PLH (patrol vessel large with helicopter) on the islands, saying the action was aimed to defend against "invasion" from Chinese marine survey ships.

(Xinhua News Agency February 5, 2009)