Three Chinese warships have been spotted in the West Philippine Sea (WPS) by the Armed Forces of the Philippines (AFP), it was bared on Monday night, Feb. 3, as China took its assertion of its claims in the South China Sea a notch higher.

The Western Mindanao Command (WestMinCom) said it was closely monitoring and tracking the movement of three People’s Liberation Army – Navy (PLA-N) vessels that entered the country’s territorial waters on Feb. 2.

The WestMinCom identified the Chinese warships as a Renhai-class Cruiser Guided Missile, a Jiankai-Class Frigate II, and a Type 903 Fuchi-Class Replenishment Oiler which navigated through Mindoro Strait towards Sulu Sea.

“It is expected that the said PLA-N vessels will be transiting through the international passages within the maritime domain of WMC – the Sibutu Passage and the Basilan Strait. As archipelagic sea lanes of communications (ASLOCs), these passages allow the transit of vessels of other nation-states subject to their compliance to national and international laws and procedures governing transits and innocent passage,” Lt. Gen. Antonio Nafarrete, commander of WestMinCom, said.

“It is noted, however, that said PLA-N vessels transited without prior diplomatic coordination and maintained unusually slow speed (4-5 knots). This is not consistent with the principles of innocent passage which requires continuous and expeditious passage and that the vessel should not linger in archipelagic waters longer than necessary,” he added.

On Feb. 3, the Philippine Navy (PN) said three Chinese warships, including a Jiankai-Class Frigate II identified as "Dali" (FFG-553), were monitored near Bajo de Masinloc, which is located 124 nautical miles from Zambales and within the 200-nautical mile exclusive economic zone (EEZ) of the Philippines but is being claimed by China.

It was not clear if the warships spotted by the Navy were the same vessels that were also monitored by the WestMinCom.

However, the WestMinCom said it deployed Philippine Air Force (PAF) Cessna 208 Caravan and Nomad N-22 aircraft to monitor the Chinese warships’ passage.

Navy vessels were also dispatched by Joint Task Force “Poseidon”, the WestMinCom’s lead maritime security arm, “to challenge and shadow the said PLA Navy vessels as they pass through WMC’s area of responsibility.”

The WestMinCom said the Chinese vessels were responsive and invoked freedom of navigation and innocent passage to justify their presence in the Philippines’ waters.

For its part, the PN said that BRP Jose Rizal (FF150) warned off and issued consecutive radio challenges to the three Chinese warships while the former was conducting patrols at approximately 57 nautical miles southeast of Bajo de Masinloc.

Since Jan. 4, China has deployed its coast guard ships, which are civilian in nature, off the coast of Zambales.

Over the weekend, two more CCG vessels were also spotted off the coast of Pangasinan by the PCG.

The Philippine Coast Guard (PCG) sees the deployment as part of China's strategy to "normalize" their presence in the area overlapping the Philippines' waters, which Beijing claims as part of its internal waters.