BEIJING, Dec 9 (Reuters) - Japan is threatening China militarily which is "completely unacceptable", Chinese Foreign Minister Wang Yi told his German counterpart, after Japan said that Chinese fighter jets had aimed their radar at Japanese military aircraft.

It is the first time the U.S. has criticized China for aiming radars at Japanese military aircraft as the diplomatic spat between Beijing and Tokyo shows no sign of easing.

China's government says Chinese nationals should avoid travelling to Japan for the time being, due to the risk of major earthquakes.

As relations with China continue to deteriorate, Japan is embarking on its biggest military buildup in at least four decades.

White House navigates backing long-time ally Japan while preserving trade truce with China amid fraying ties between the Asian neighbours.

Kumamon’s playful exchanges with crowds come amid a diplomatic spat between Tokyo and Beijing, which has sparked fears that Japan’s travel sector could be affected.

China and Japan are two of Asia’s most powerful nations and the region’s biggest trading partners. Yet centuries of intense rivalry mean their economic embrace can never be taken for granted.

Japanese Defense Minister Shinjiro Koizumi acknowledges radio communication with Chinese side but rues lack of ‘concrete information’ about Chinese naval drills - Anadolu Ajansı