China criticized Japan on Tuesday for making "groundless accusations" against Beijing in its annual defense white paper.
The Chinese Defense Ministry said in a statement the content of the report was "deliberately exaggerating China's threat" to give Japan an "excuse" to adjust its security policy and expand arms production.
"China expresses firm opposition," it said of the report released by the Defense Ministry and approved by Prime Minister Shinzo Abe's Cabinet earlier in the day.
The white paper, titled the Defense of Japan 2014, says China's growing assertiveness at sea and in the air is posing threats to regional stability, noting its abrupt establishment last November of an air defense identification zone (ADIZ) over a large swath of the East China Sea where the Japan-controlled Senkaku Islands are located.
"Japan has great concerns over such Chinese military activities . . . together with the lack of transparency in its military affairs and security issues, and needs to pay utmost attention to them," the annual report says.
Relations between Japan and China remain soured over control of the Senkaku Islands and differences over wartime history.