The move comes against the backdrop of rising tension between the Philippines, a U.S. treaty ally, and Beijing.

Philippines vows not to back down from Beijing's increasingly aggressive South China Sea patrols which it says were moving alarmingly close to the country's coast. National Maritime Council Spokesman Jonathan Malaya says in a press conference that China is "increasing aggression" by deploying "monster ship" China Coast Guard vessel 5901 about 77-nautical-miles off the coast of the Philippines' largest island.

The Philippines on Monday said it filed a diplomatic protest to counter China’s “continued illegal presence and activities” within Manila’s exclusive economic zone in the South China Sea.

Manila calls the presence of the Chinese vessel 'illegal' and 'unacceptable', deploying two of the Philippine Coastguard's largest ships to drive it away

The Philippines said a huge Chinese coast guard ship widely known as the “Monster” has returned to its exclusive economic zone in the South China Sea, prompting its own coast guard vessel to approach and issue a radio challenge.

The National Maritime Council is urging the Chinese government to withdraw its'monster ship' from the Philippine's exclusive economic zone.