Both the Philippines and Vietnam made the move following a standoff between Chinese and Vietnamese ships in the disputed waters. According to South China Morning Post, concerns have been brewing around the number of Chinese coastguard ships placed in the seas. Some say that the numbers are part of a bid to increase China’s claims to the waters.
Reports suggest that China could continue to escalate its numbers.
However, the Philippine Coast Guard confirmed that a French-made offshore patrol vessel, alleged to be the “biggest and most modern” of its kind, had been sent to bolster its fight.
Laws were also passed in Vietnam allowing the country’s coastguard to operate outside of its territorial waters in the South China Sea.
It comes just days after Vietnam ordered Beijing to withdraw an oil vessel from the waters.
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The ship’s presence appears to have caused the rift as countries such as Vietnam sent their own vessels to assess the situation.
Vietnamese foreign affairs ministry spokesperson Le Thi Thu Hang said: “Over the last several days, the Chinese survey ship, Haiyang Dizhi 8, and its escorts conducted activities in the southern area of the East Sea that violated Vietnam’s exclusive economic zone and continental shelf.
“This area lies entirely within the Vietnamese waters.”
Ms Hang also added that China’s actions were “unlawful activities” which must be stopped.
Local reports suggest that six “heavily armed” coastguard vessels from both Vietnam and China had been in each other’s gaze since the start of July.
Tensions over the water have been boiling in recent months, with arguments escalating between the US and China.
Fears of open conflict over the South China Sea have also been raised.
China claims the waters, but Malaysia, Brunei, Vietnam, Taiwan and the Philippines also believe it is theirs.