Japan will shortly replace its ambassadors to China, South Korea and the United States in an unusual simultaneous move amid difficulties in Tokyo’s dealings with all three, reports said.
Japanese media has also reported in the past few days the planned replacements of ambassadors in Seoul and Washington.
The government is expected to officially announce the moves after the current session of parliament ends on September 8, Kyodo news agency has reported.
The foreign ministry declined to comment on the reports.
Tokyo’s territorial row with Beijing flared up anew as activists from Hong Kong landed on Japan-administered islands in the East China sea claimed by China. They were followed days later by Japanese nationalists.
Separately, South Korean President Lee Myung-Bak visited islets in the Sea of Japan (East Sea) controlled by his country but claimed by Japan, sending relations plunging.
Tokyo’s ties with Washington have also stalled over the relocation of a major US military base on the Japanese island of Okinawa.
Niwa sparked controversy in June when he expressed objections to the Tokyo municipal government’s plan to buy disputed islands, saying the move could spark an “extremely grave crisis” between the Asian powers.