Chinese Foreign Ministry spokesman Lu Kang drinks a cup of water at a regular news conference in Beijing, October 27, 2015. REUTERS/Kim Kyung-Hoon

BEIJING (Reuters) - China said on Thursday it had complained to the United States about the signing into law of an act which authorizes the possibility of mutual visits by navy vessels between self-ruled Taiwan and the United States.

Chinese Foreign ministry spokesman Lu Kang told a daily news briefing that China was firmly opposed to the Taiwan content in the act.