In a report on China's military power, the Pentagon asserted Monday that Beijing's reluctance to share details about its military buildup poses a risk to stability in Asia.

The report said the international community has limited knowledge of the motivations, decision-making and capabilities supporting China's military modernization. This includes a lack of clarity about China's defense spending, which Washington contends China understates.

"The lack of transparency in China's military and security affairs poses risks to stability by increasing the potential for misunderstanding and miscalculation," the report said. "This situation will naturally and understandably lead to hedging against the unknown."

The military buildup in China has increased in recent years, the Pentagon said.

"China's expanding and improving military capabilities are changing East Asian military balances; improvements in China's strategic capabilities have implications beyond the Asia-Pacific region.," the report said.