The heat over the islands dispute in the East China Sea has been turned up further, with China sending fighter jets and an early warning aircraft into an area that the country last week designated as an Air Defense Identification Zone.
China's action follows the U.S., Japan and South Korea sending military planes into the region without telling Beijing first, in defiance of the latter's directives that they should provide prior notification.
However, China also played down the threat of the military action it had threatened against aircraft that hadn't informed it of their intentions.
China and Japan lay claim to the islands, which are known as Senkaku in the latter country and Diaoyu in China. The last flare-up a year ago caused much damage to trade between the nations.