Japanese Ambassador to the Philippines Koshikawa Kazuhiko criticized China's '' dangerous behavior in the South China Sea in defiance of the 2016 arbitration award.''

The ambassador, in a Twitter account, said this ''is a grave concern for regional peace and stability.''

Koshikawa made this statement following an incident on June 30 where the Philippine Coast Guard claimed Chinese Coast Guard ships tried to block a resupply mission to troops at a grounded vessel in Ayungin Shoal.

''During the operation, the PCG was constantly followed, harassed, and obstructed by the significantly larger Chinese Coast Guard vessels at a distance of approximately 100 yards,'' said Commodore Jay Tarriela, PCG spokesperson for the West Philippine Sea, in his Twitter account.

Tarriela added that the ''PCG is deeply concerned about the presence of two PLA-N (People's Liberation Army-Navy) vessels in Ayungin Shoal.''

''This is particularly alarming as the Philippine Navy's naval operation is solely humanitarian in nature,'' said Tarriela. DMS