The U.S. State Department is advising U.S. air carriers to comply with China's demand that it be told of any flights passing through its new maritime air defence zone over the East China Sea, the Associated Press reported.

Last week China declared that all aircraft entering the zone must notify Chinese authorities beforehand, and warned that it would take unspecified defensive measures against those that do not comply.

Some neighbouring countries and the U.S. have said they will not honour the new zone and that it unnecessarily raises tensions.

State Department spokeswoman Jen Psaki said yesterday that the U.S. remains deeply concerned about China's declared air identification zone.

But she says that it is advising U.S. air carriers abroad to comply with notification requirements issued by China.