JAKARTA (Reuters) - Indonesia's military said on Thursday that Chinese coast guard vessels and fishing boats had left disputed waters in the western reaches of the South China Sea following a visit by President Joko Widodo to assert his nation's sovereignty.
During recent weeks, Jakarta summoned China's ambassador after the coast guard and fishing boats entered waters around the northern Natuna islands, where Indonesia has established an exclusive economic zone.
Indonesia stepped up air and sea patrols in the area, and on Wednesday Widodo visited one of the islands to drive home the message that it was Indonesian territory, at which point, his military said, the Chinese vessels quit the area.
"From the observation of our planes, they're no longer there," military spokesman Major General Sisriadi told Reuters on Thursday. "They left as soon as the president arrived on the Natuna."
Nursyawal Embun, director of sea operations at the Maritime Security Agency, said, however, that one ship -- HAIJING35111 -- was still in the "Indonesian continental shelf waters."
China has not claimed the Natuna islands themselves, but says it has nearby fishing rights within a self-proclaimed Nine-Dash Line that includes most of the energy rich South China Sea - a claim disputed by some Southeast Asian countries and isn't recognised internationally.
In 2017, Indonesia renamed the northern section of its exclusive economic zone as the North Natuna Sea, as part of a push back against China's maritime territorial ambitions.
On Wednesday, Chinese foreign ministry spokesman Geng Shuang said Beijing and Jakarta are in contact through diplomatic channels to "deal with differences and uphold peace and stability in bilateral relations and the region".
Sisriadi said Indonesia's navy would continue operations in the area.
(Reporting by Agustinus Beo Da Costa and Stanley Widianto; Editing by Gayatri Suroyo and Simon Cameron-Moore)