Japan said it was not tolerating any action that would raise tension in the South China Sea after the Philippines accused China of attacking one of its supply ships with a water cannon in the waters off Ayungin Shoal.

In a statement on X, Japanese Ambassador to the Philippines Koshikawa Kazuhiko said Tokyo is giving "high importance to a free and open maritime order" based on the rule of law, as what Japan and the Philippines discussed during Kishida's visit to Manila last week.

"Any harassment and actions which increase tensions are not tolerated," Koshikawa said.

This statament came only several days after Tokyo upgraded its security ties with Manila to ensure a free and open Indo-Pacific.

On Nov. 3, the Philippines and Manila entered into a bilateral security agreement that would start their talks on a possible Reciprocal Access Agreement (RAA)—an agreement that looks the same with what Manila has with Washington.

Such an agreement would allow both countries to share with each other military training and operations, among others, in line with Tokyo's aspiration to realize an open and free Indo-Pacific amid the current situation in the West Philippine Sea and the bigger South China Sea.

Japan's warning came after China allegedly hit for the second time this year a Philippine resupply boat in the waters off Ayungin Shoal with a water cannon, which became the subject of the Philippines 58th diplomatic protest against Beijing in 2023 alone.

Japan was not alone in backing the Philippines. At least seven other nations and the European Union came to support Manila, which lamented China's harassment in the waters.

German Ambassador to the Philippines Andreas Pfaffernoshke, Australian Ambassador HK Yu, UK Ambassador Laure Beaufils and EU Ambassador Luc Veron called for respect for international law in the South China Sea following the latest incident.

"The UK notes unsafe conduct again experienced by the Philippine vessels on their resupply mission to Ayungin Shoal. We join the Philippines in calling out actions that undermine peace & stability in SCS.  We are committed to UNCLOS (United Nations Convention on the Law of the Sea), under which 2016 Arbitral Award is final and legally binding on both parties," Beaufils said.

Meanwhile, New Zealand Ambassador Peter Kell and Canadian Ambassador David Hartman expressed their respective concern over the water cannon attack.

Hartman said the action was the latest of "a series of escalating acts of intimidation" that also "undermines regional peace and stability."

US Ambassador MaryKay Carlson and French Ambassador Marie Fontanel then lauded the successful resupply operation of the Philippine boat to the beached BRP Sierra Madre despite the "dangerous" and "deliberate obstacles" in the country's exclusive economic zone.