A Japan-North Korea summit may take place in early June. Japan's Asahi Shimbun reported Thursday that training material produced by the North Korean Workers Party contains a reference to that effect.

The training document hails leader Kim Jong-un's diplomatic prowess and explains his goals involving relations with South Korea, the U.S., China, Japan and Russia.

"The Japanese government has been voicing its intention to hold talks through Chongryon," a pro-North Korean residents group in Japan. "The Japan-North Korea summit will be held in Pyongyang in early June following the U.S.-North Korea summit in May."

Japanese Chief Cabinet Secretary Yoshihide Suga said Tokyo is communicating with Pyongyang through the Japanese Embassy in China and other channels but did not elaborate.

