The United States says China has the right to sail in international waters after a Chinese aircraft carrier cruised past Taiwan and into the contested South China Sea.
Taiwan's Defense Ministry reported on Monday that the aircraft carrier and five warships sailed 90 nautical miles south of Taiwan, a self-governing island claimed by China.
Beijing says it is a routine training exercise.
China has previously accused US warships of making provocative passes through the South China Sea.
State Department spokesman Mark Toner said on Tuesday the US recognises lawful uses of the sea, and the same rights apply to the US, China and other nations.
He said, "as we often make the case with our own naval vessels sailing ... in those same waters, it's freedom of navigation."
Earlier this month, a Chinese navy vessel seized a US Navy underwater glider that the US said was conducting oceanic research in international waters off the Philippines.
The US called the seizure illegal and made a diplomatic protest. China returned the glider five days later.
Beijing claims most of the South China Sea. Five other Asian governments also claim ownership of islands and reefs there.
