China says there's no problem with freedom of navigation in the South China Sea.
It comes after a radio recording has emerged of a Royal Australian Air Force surveillance plane conducting a freedon of navigation flight over the South China Sea.
The audio, published by the BBC, reveals a RAAF pilot speaking to the Chinese Navy as he flies over the disputed South China Sea.
"China navy, China navy, we are an Australian aircraft exercising international freedom-of-navigation rights in international airspace in accordance with the International Civil Aviation Convention and the United Nations Convention on the Law of the Sea, over."
Chinese Foreign Ministry spokesman Hong Lei says other countries should not complicate the issue.
"I want to declare once again that there is no problem with freedom of navigation, and overflight in the South China Sea. Countries outside the region should respect other countries' sovereignty and not deliberately complicate the issue."
Satellite imagery shows that China is building seven man-made islands on reefs in the Spratly Islands, including a 3 thousand metre long airstrip on one of the sites.
China claims most of the South China Sea, through which more than $5 trillion of world trade ships every year, a fifth of it heading to and from U.S. ports
