US vice-president Joe Biden will tell Chinese leaders next week the recent establishment of an air defence zone is “unsettling” its neighbours and raises questions about its broader international behaviour.

Mr Biden is expected to use a week-long visit to Asia starting on Sunday to press China about last weekend’s announcement of a new set of flight restrictions over an area including a disputed chain of islands in the East China Sea.

China’s foreign ministry defended the decision yesterday, saying it was a “legitimate action taken to safeguard its legitimate rights”. However, the US has already challenged the move by flying a pair of B52 bombers through the area, and the new Chinese rules are being widely flouted by Japanese airlines. South Korea, Taiwan and Australia have also criticised the move.