By Stanley Widianto

JAKARTA (Reuters) – A Chinese coast guard vessel was driven out of Indonesia’s waters for a second time this week after it initially disrupted a survey by state energy firm Pertamina in the South China Sea, Indonesia’s maritime security agency said on Thursday.

While Chinese coast guard vessels have been spotted numerous times in Indonesia’s exclusive economic zone (EEZ), the most recent incidents came just days after Prabowo Subianto took over Indonesia’s presidency.

China claims sovereignty over almost the entire South China Sea via a “nine-dash line” on its maps that cuts into the EEZs of Malaysia, Brunei, the Philippines, Indonesia and Vietnam.

The Permanent Court of Arbitration in the Hague in 2016 said China’s claim has no basis under international law, a ruling Beijing does not recognise.

The incidents took place off Indonesia Natuna islands, roughly 1,500 km (932 miles) from China’s Hainan island. The exact locations were not immediately clear.

The Chinese vessel on Monday insisted the area was China’s jurisdiction, Indonesia’s maritime security agency, known as Bakamla, said in a statement.

China’s foreign ministry did not immediately respond to a request for comment.

“Bakamla will keep patrolling and intensively monitoring the waters of North Natuna to ensure seismic data gathering can go without disruption to Indonesia’s sovereignty,” the agency said on Monday.

On Thursday, it said the Chinese vessel returned but was intercepted and again driven out. It did not provide details on what the ship was doing.

China asserts its claim of sovereignty via an armada of coast guard ships deployed throughout the South China Sea, some of which are accused by its neighbours of aggressive conduct and of trying to disrupt energy and fisheries activities.

China typically says its coast guard operates lawfully to deter territorial infringements in what are its waters.

In 2021 vessels from Indonesia and China shadowed each other for months near a submersible oil rig that had been performing well appraisals in the Natuna Sea. China at the time urged Indonesia to stop drilling in what was its territory.

The latest incidents came as Indonesia’s new defence minister, Sjafrie Sjamsoeddin, met with China ambassador in Jakarta on Thursday.

The defence ministry in a statement said Sjafrie expected to boost defence cooperation with China, including joint exercises. It made no mention of this week’s maritime incidents.