Updated

China is stressing mutual respect and cooperation in response to tough talk from Donald Trump's pick for U.S. secretary of state, who said the administration will block Chinese access to its fortified man-made islands in the South China Sea.

Foreign Ministry spokesman Lu Kang said Thursday that tensions in the strategically vital waterway have lessened and countries from outside the region should support efforts toward stability.

Former Exxon Mobil CEO Rex Tillerson said Wednesday the U.S. needs to send China a "clear signal" that its island building will have to stop. He said China's access to islands already built wouldn't be allowed, but didn't mention specifics.

Chinese diplomats say they aren't overly worried by fiery rhetoric from Trump and his Cabinet picks and that China won't change its basic approach.