Tokyo released on July 31 this year's edition of its annual defense white paper, which plays up China's regular fishery patrols in the waters off China's territorial Diaoyu Islands.

Japanese Defense Minister Satoshi Morimoto delivered a speech over the Defense of Japan 2012 report to his cabinet during a morning meeting in Tokyo.

China has regularly sent fishery administration vessels to the islands' waters for routine patrols, yet the white paper accuses China of "intruding" on its "territorial waters", Japan's Jiji Press News Agency said.

The defense report also sent warning signals over Beijing's "continuous enhancement of maritime patrols".

Japanese Prime Minister Yoshihiko Noda said in early July that his cabinet is seeking to "nationalize" part of the Diaoyu Islands, a move that has added to tension.

Beijing has lodged solemn representations with Tokyo saying that "nobody is ever allowed to trade in China's sacred territory".

Three Chinese administration vessels were confronted by a Japanese Coast Guard patrol ship in waters near the Diaoyu Islands on July 11 during a regular mission.