A defence policy report approved by the Japanese government on Tuesday has inflamed tensions with China by describing Beijing's military activity in the East and South China Seas as a threat.
The 480-page white paper, which outlines defense strategy changes since last July, also makes "irresponsible remarks" on China's actions in the East and South China Seas, "smearing China's normal maritime activities to justify Japan's own militarization," Chinese state news agency Xinhua reported on Tuesday.
Chinese naval aircraft, submarines and ships launched a new manoeuvre in the East China Sea on Monday, state media reported, firing rockets and torpedoes in the waters where China and Japan are locked in a dispute over a group of unoccupied islands.
The military drill aims to enhance the "intensity, precision, stability and speed" of troops, according to a Monday navy statement quoted by Xinhua.
The two neighbouring countries have overlapping claims over islands in the East China Sea known as Diaoyu to Beijing and Senkaku to Tokyo.
Last month, the Permanent Court of Arbitration in The Hague upheld a complaint brought by the Philippines about contested islets claimed by China in the South China Sea. The body of water contains key shipping routes and is believed to be rich in mineral and marine resources.
Analysts say the court's decision against China put Japan in a stronger position in its own territorial dispute.