Indonesia yesterday defended its navy for firing warning shots at a fleet of 12 Chinese fishing boats caught poaching in its waters off the Natuna Islands last week.

Coordinating Minister for Political, Security and Legal Affairs Luhut Pandjaitan told The Straits Times that the shooting at sea was in accordance with rules of engagement.

His remarks follow China's protest on Sunday over the capture of the Chinese fishing boat Yueyandong Yu 19038 and its crew of seven by the Indonesian warship KRI Imam Bonjol last Friday.

Beijing also complained that a Chinese fisherman from another China-flagged vessel was wounded, purportedly by shots fired by the KRI Imam Bonjol during Friday's skirmish. Mr Luhut, however, said there was no need for Indonesia to respond to the protest.

"What is important is that we find a solution amicably, we want to maintain good relations with China, but without sacrificing our sovereignty," he said.

Separately, Indonesia's Maritime Affairs and Fisheries Minister Susi Pudjiastuti said in a series of tweets yesterday that the Indonesian warship was right in safeguarding the sovereignty of its waters. "We don't shoot for no clear reason," she tweeted. "Protecting (the) sovereignty of your country is a must."

The Yueyandong Yu was among a fleet of 12 Chinese vessels the navy had detected fishing illegally in Indonesia's exclusive economic zone (EEZ) last Friday.

Warships deployed to intercept the poachers fired warning shots across the fishing boats' bow as they tried to evade capture. Only the Yueyandong Yu was detained after a short pursuit.

An EEZ is a zone extending 200 nautical miles from shore over which a state has special rights regarding the exploration and use of marine resources under the United Nations Convention on the Law of the Sea. The EEZ of a handful of littoral states in the South China Sea overlap with China's nine-dash line, feeding into the territorial disputes between the Asian powerhouse and Taiwan as well as Vietnam, the Philippines, Malaysia and Brunei in South-east Asia.

Indonesia was never a party to the dispute, but it was recently dragged into a similar territorial fracas with China, after Beijing said in March that the waters in Indonesia's EEZ are part of its "traditional fishing grounds". Mr Luhut said Jakarta has never acknowledged Beijing's claim of the traditional fishing grounds in Indonesia's waters but he hopes to "continue discussing with international maritime law experts to find an elegant way of resolving" the issue.

According to presidential spokesman Johan Budi, President Joko Widodo yesterday echoed Mr Luhut's stand that Indonesia will steadfastly defend the sovereignty of Indonesia, but without affecting its ties with other countries.

"Our sovereignty is non-negotiable and must be defended," said Mr Johan. "However, as Pak Luhut stated, we also need to maintain our relations, not only with China, but also with other countries."

China's Foreign Ministry spokesman Hua Chunying yesterday again condemned Indonesia's "indiscriminate use of force".

"We urge the Indonesian side to refrain from any action that complicates or magnifies the dispute, or impacts the peace and stability of the region," she told Reuters.