Japan has called for calm in the wake of China's apparent decision to suspend top-level ties over a territorial row.
A government spokesman said Japan had not yet been formally informed of the move but urged China to act prudently.
On Sunday Chinese media said ministerial and provincial-level contacts had been suspended.
It followed Japan's decision to extend the detention of the captain of a Chinese trawler accused of hitting two Japanese vessels in waters both claim.
Japan has a further 10 days to either charge or release the captain. The fishing boat's 14 Chinese crew were released last week.
The incident on 7 September happened near uninhabited islands known as Senkaku in Japan and Diaoyu in China.
BBC News
