China's rapid military build-up is a direct threat not only to Taiwan but to the United States, Japan, and Australia as well, Taiwan President Chen Shui-bian warned in an interview published on Saturday.

"Some of their missiles can reach 10,000 kilometres," Chen told The Weekend Australian in Taipei.

"Therefore, their targets include the US, Japan, Australia - all the countries in the Asia-Pacific region," he said, adding that Beijing was also strengthening its worldwide espionage operations.

An estimated 600-700 ballistic missiles along the Chinese coast face Taiwan, just 160 kilometres away.

China and Taiwan split amid civil war in 1949. China claims the island as its territory and passed a law earlier this year, authorising the use of force if Taiwan moves toward formal independence. Taiwan, on the other hand, holds annual military exercises that include simulations of a Chinese invason.

Chen's comments echoed a Pentagon report, published last month, which said that Chinese military planners wanted to expand beyond their immediate goal of dominating Taiwan.

The report said that an increasingly modern Chinese military could pose a threat to the US and other forces. Governments across Asia worry about Beijing's growing military power, driven by a booming economy and double-digit annual spending increases.

China's military-spending is already the world's third-highest at US Dollar 50 billion to US Dollar 70 billion a year, behind only to US and Russia, the Pentagon report had said.

Also read: China's nuke warning to US on Taiwan