Facts

• Indonesia's naval chief announced on Saturday that the country has sent a warship, maritime patrol plane, and drone to its North Natuna Sea to monitor a Chinese coast guard vessel sailing in its exclusive economic zone (EEZ) for the past two weeks.^[1]
• China's CCG 5901 — the world's largest coast guard vessel nicknamed "the monster" for its size — has reportedly been sailing near Indonesia's Tuna Block gas field and Vietnam's Chim Sao oil and gas field since Dec. 30.^[2]
• This comes shortly after Jakarta approved a $3B plan to develop the Tuna offshore gas field, which is expected to export gas to Vietnam by 2026 and reach a peak production capacity of 115M standard cubic feet per day by 2027.^[3]
• Indonesia claims that under the UN Convention on the Law of the Sea (UNCLOS) — which grants international vessels navigation rights through an EEZ — the North Natuna Sea, or the southern end of the South China Sea, is part of its EEZ.^[4]
• But China claims the resource-rich maritime region rests within its expanded territory in the South China Sea, marked by a U-shaped "nine-dash line."^[4]
• In 2021, China and Indonesia clashed over an oil rig that had been conducting tests in Indonesia's gas-field development area, with China claiming the drilling was taking place in its territory.^[2]