After Indian and Philippines conduct joint patrol in the South China Seas, China remains on High Alert.

China is on high alert for India’s involvement in South China Sea, after the first-ever joint patrol between India and the Philippines in the strategically important waters, which observers say may further complicate relations between India and China. The assessment was made as Indian and Philippine navies on Monday wrapped up their Maritime Cooperative Activity (MCA), which coincided with a state visit by Philippine President Ferdinand Marcos Junior to India. The MCA involved three Indian naval vessels, including a guided missile destroyer and an anti-submarine corvette.

Two Philippine Navy warships, including BRP Miguel Malvar, a guided missile frigate that was commissioned in May, also took part in the two-day patrol that “spanned strategic waters” from Masinloc in Zambales province to Cabra Island in Occidental Mindoro and highlighted “the growing security collaboration between the two Indo-Pacific partners”, the Armed Forces of the Philippines (AFP) said on social media.

Masinloc is a town on the Philippines’ main island of Luzon, just 124 nautical miles (230km) east of Scarborough Shoal, a triangle-shaped chain of reefs and rocks that is at the centre of the recent maritime confrontations between Beijing and Manila. On Monday, AFP chief of staff General Romeo Brawner Junior told local media that “several” Chinese vessels had been spotted during the patrols.

The PLA would “remain on high alert at all times, resolutely safeguarding national territorial sovereignty and maritime rights and interests, and any military activities aimed at disrupting the South China Sea or creating tensions are fully under control”, Tian Junli, the spokesman of the PLA Southern Theatre Command, said in the statement.

Bao Yinan, an associate research fellow at the Huayang Centre for Maritime Cooperation and Ocean Governance in Hainan, said whether the joint patrols had crossed China’s designated 12-nautical-mile baseline around the shoal would “be a key issue for China to monitor”. He was referring to the geographic coordinates China announced in November around Scarborough Shoal – known as Huangyan Island in China and Panatag Shoal in the Philippines – in response to the introduction in Manila of two laws that aimed to strengthen Philippine maritime claims in the South China Sea.

Zheng Zhihua, an associate professor specialising in maritime affairs at Shanghai Jiao Tong University, said Beijing had strengthened its control over the disputed shoal with more frequent maritime exercises and patrols since the baseline announcement. “As a result, Manila appears to be seeking the backing of external powers to enhance its leverage in negotiations and to counterbalance China”, Zheng said. He added that Beijing was expected to take tougher action if the activities took place within the 12 nautical mile baseline, but if they remained in waters far from the shoal, Beijing might simply carry out routine monitoring.

Benjamin Blandin, an expert in maritime security and research fellow at the Yokosuka Council on Asia-Pacific Studies, said the latest patrols meant India had joined the three other Quad nations in getting involved in the maritime row “at a significant level”. Quad members the United States, Australia and Japan have previously joined the Philippines in bilateral patrols in the contested waters, which have also drawn protests from Beijing. China sees the four-way grouping as an attempt by the US to encircle China with strategic and military allies and partners. “To China, all lights seem to be turning red, and no improvement is in sight … which might lead China to be even more aggressive against its direct neighbours”, Blandin said.

According to maritime analysts, the first joint patrol signalled India’s growing alignment with Manila on the maritime dispute, as it went beyond the simple tactical manoeuvres and passage exercises that the Indian navy had previously undertaken in the region. It underlines the fact that India has now aligned more closely with the Philippines in its dispute with China. India initially took a cautious stance over the 2016 South China Sea arbitration ruling, which determined that China’s claims in the South China Sea were unfounded under international law. But it had revised its position in 2023 when India underscored the need for “adherence” to the decision. Last year, this commitment deepened further when Delhi’s then foreign minister reiterated India’s support for the Philippines in safeguarding its national sovereignty.

The MCA backs up this pro-Philippine diplomatic posture with concrete actions on the ground, adding that both Manila and Delhi derived benefits from their growing engagement. India views the security of maritime sea lines as critical to their economic prosperity and continued growth. The Philippines sees India as a potential and reliable defence partner.

Blandin said New Delhi viewed deeper engagement with claimant nations as a strategic and cost-effective means to counterbalance China’s activities in the Indian Ocean while strengthening India’s ties with Southeast Asia.

It was in 2022, the Philippines became the first foreign nation to acquire India’s BrahMos supersonic cruise missiles under a US$375 million deal, with the first of the three batches delivered last year. In April, Philippine Defence Secretary Gilberto Teodoro Junior said a second batch of the missiles was set to be delivered soon. Observers said it remained to be seen how much strain the joint patrols would put on relations between China and India. Boosting defence ties with India is expected to be high on the agenda for Marcos during his four-day visit.

Team India