Japan's annual defense report stresses the need to introduce a new ballistic missile defense system, citing nuclear and missile threats from North Korea.
The white paper was reported to the Cabinet on Tuesday.
It notes that it was significant that North Korean leader Kim Jong Un clearly committed to denuclearizing the Korean Peninsula in his June 12th summit with US President Donald Trump.
But it says the North remains an unprecedented, serious and immediate threat.
It refers to the country's deployment of ballistic missiles within range of Japan, and its nuclear and missile development that shows increasing operational capacity.
The report says Japan is set to strengthen its capabilities to counter ballistic missile attacks. It says introducing the new ground-based ballistic missile defense system Aegis Ashore will dramatically enhance the nation's defence.
The paper describes China as a security concern to the region and to the world, saying it is unilaterally escalating activities in areas around Japan.
China has been increasing its maritime activities in the South China Sea and other waters.