China and South Korea cancelled visits to Japan for high-level talks raising questions on how well the three countries can work together to contain North Korea.

Guo Boxiong, China’s Central Military Commission and highest ranking military officer, put off the visit for “official reasons”. The cancellation came after rising tensions in Sino-Japanese relations provoked by the Uighur conference in Tokyo and the territorial dispute in the East China Sea.

The Uighurs are an exiled minority ethnic group from China. Both countries claim the Senkaku/Diaoyu Islands, the subject of recent high-level maritime talks.

Japan and South Korea were to sign a military accord that would let the two countries share intelligence on North Korea. South Korean Defense Minister Kim Kwan-jin was reluctant after opposition feared provoking North Korea and China. Closer military ties with Japan could put them on the Chinese radar. Moreover, the issue of “comfort women” in the Imperial Japanese war still remains.

The three East Asian nations also discussed a trilateral free trade agreement.