A file photo of Foreign Ministry spokesperson Guo Jiakun. [Photo/fmprc.gov.cn]

China firmly opposes any act of provocation by any country under the pretext of freedom of navigation, Foreign Ministry spokesperson Guo Jiakun said here on Wednesday.

Guo made the remarks at a daily news briefing in response to the U.S. warships' transit through the Taiwan Strait this week, saying that the Chinese People's Liberation Army (PLA) Eastern Theater Command has issued a response.

Guo stressed that Taiwan is an inalienable part of Chinese territory, and the Taiwan question is not about freedom of navigation but about China's sovereignty and territorial integrity.

"The Chinese side firmly opposes any attempt by any country to make provocations and threaten China's sovereignty and security under the pretext of freedom of navigation," Guo said.