China's primary security priority is to block efforts by Taiwan toward permanent separation and prevent Japan's further military cooperation with the United States, the Pentagon said in a report Friday.

The Pentagon made the assessment in its annual report on the military power of China, which was presented to Congress under the national defense authorization act of fiscal 2000.

Beijing "seeks to counter what it perceives to be Japan's growing military cooperation with the United States," the report said.

The strategy is aimed at preventing "a rebirth of Japanese militarism," it said.