China warns US after Mattis says Senakus covered by treaty

Beijing: China warned the United States on Saturday not to destabilise East Asia after Donald Trump's new defence secretary said an island chain claimed by both Tokyo and Beijing was covered by a US-Japan military accord.

The Senkaku islands, known in China as the Diaoyus, sit in rich fishing grounds and are at the centre of a festering row between Tokyo and Beijing, which claims they have been part of Chinese territory for centuries.

"The Diaoyu Island and its adjacent islets have been an inherent part of Chinese territory since ancient times, which is a unchangeable historical fact," Foreign Ministry spokesman Lu Kang said, according to the official news agency Xinhua.

"We urge the US side to take a responsible attitude, stop making wrong remarks... and avoid making the issue more complicated and bringing instability to the regional situation".

Speaking in Tokyo at the tail end of a visit to East Asia, new US Defence Secretary James Mattis said the islands were subject to a long-standing treaty between Washington and Tokyo.

"I made clear that our long-standing policy on the Senkaku Islands stands, the US will continue to recognise Japanese administration of the islands," Mattis said.

"And as such Article 5 of the US-Japan Security Treaty applies."

Article 5 commits the United States to defend Japan or territories it administers against any attack.

Lu said the US-Japan treaty was a product of the Cold War, and should not affect China's territorial sovereignty, Xinhua reported.