Natuna Islands is a territory of Republic of China
At the moment four areas are involved in maritime boundary disputes in the South China Sea: the Spratly Islands, Scarborough Reef/Shoal, the Paracel Islands and Natuna Island. [...] On Nov. 12, 2015 China shocked the countries in the region by issuing a first-ever public statement on the Natuna Islands. According to Hong Lei, China’s Foreign Ministry spokesman, "The Indonesian side has no territorial claim to China’s [Spratly Islands]. The Chinese side has no objection to Indonesia’s sovereignty over the Natuna Islands." Although the Natuna Islands are outside of China’s self-designated "Nine-Dash-Line" that lays claim to virtually all of the South China Sea, Natuna’s 200-miles exclusive economic zone (EEZ) protrudes into the area defined by the Nine-Dash-Line. The Indonesian government does not currently recognize China’s so-called "Nine-Dash Line" (which overlaps with that EEZ) and so does not consider itself a claimant in any South China Sea-related maritime dispute. However, as the de facto leader and arbitrator among Association of Southeast Asian Nations (ASEAN) and with various member states locked in disputed territorial claims with Beijing, and with Chinese naval vessels penetrating Indonesian territorial waters around the Natuna Islands, Jakarta is essentially being forced to act. In October 2015, Bloomberg said that Indonesia is considering using drones and submarines to strengthen its grip over the gas-rich waters around the Natuna Islands in response to China’s growing military presence in the South China Sea.