Ashton Carter, the US defence secretary, told Chang Wanquan, his Chinese counterpart, yesterday that the US would continue to conduct naval operations in the South China Sea, which Beijing considers to be “illegal”.

During a meeting that US officials described as “cordial”, Gen Chang told Mr Carter that China would defend what it considers to be sovereign territory and had a “bottom line” when it came to US missions in the South China Sea.

The differences were aired when the defence leaders met for the first time on the fringe of a South East Asian summit in Malaysia. Their conversation came a week after a US destroyer sailed within 12 nautical miles of an artificial island in the South China Sea that is claimed by China and where it is building an airfield that could have military use.