Defense Ministry spokesman Yang Yujun on Thursday confirmed that Chinese naval ships have carried out patrolling and military training in waters off the Diaoyu Islands recently.

Yang's confirmation was made in response to a media request following reports by Japanese media last week of two Chinese naval frigates navigating waters off the Diaoyu Islands.

Yang said the Diaoyu Islands have been an inseparable part of Chinese territory since ancient times and it is legitimate for Chinese naval ships to carry out patrolling and training for military readiness in waters under Chinese jurisdiction.

The Chinese military shoulders the responsibility of safeguarding national territory and state sovereignty as well as its maritime rights and the safety of its people, according to the spokesman.

"Chinese troops perform a duty of military readiness to quickly react to maritime and airspace emergencies and closely work with the departments of maritime surveillance and fishery administration to provide security for the country's maritime law enforcement, fishery production as well as oil and gas development," he said.

When asked to comment on Japanese right-wingers' clamor for upgrading the Japanese Self-Defense Forces to normal national defence forces, Yang pointed out that the war of aggression by Japanese militarists had brought severe disasters to Asian people.

"Japan should learn from history and strictly keep to a purely defensive policy to build trust with its neighboring countries and the international society," he said.