Japan warned Beijing of consequences if a Chinese naval vessel near the disputed Senkaku Islands in the East China Sea intruded into Japanese territorial waters there this month, government sources said Saturday.
The warning, conveyed by then Vice Foreign Minister Akitaka Saiki to Chinese Ambassador Cheng Yonghua early on June 9, is thought to have related to the possible mobilization of Maritime Self-Defense Force vessels for maritime security operations.
Such operations can be ordered by the defense minister to respond to situations deemed difficult for the Japan Coast Guard to cope with. The use of arms is permitted, although conditionally.