The Association of Southeast Asian Nations on Tuesday began the bloc's first joint military exercises in Indonesian waters amid increasing tensions over China's assertiveness in the nearby South China Sea.

The five-day drills around Indonesia's Natuna Islands are focusing on humanitarian assistance and disaster relief rather than combat operations, said Indonesia, this year's ASEAN chair. Indonesia, Malaysia, Singapore, Brunei and Thailand have sent military personnel.

The opening ceremony for an ASEAN joint military exercise is held on Indonesia's Batam Island off Singapore on Sept. 19, 2023. (Kyodo)

Indonesian military chief Adm. Yudo Margono put aside views that the drills are being held in response to tensions over a new map recently released by Beijing laying claim to contested waters of the South China Sea.

He told reporters, however, that the 10-member ASEAN will remain "united" and that is needed to ensure regional stability.

In the South China Sea, some ASEAN members have become increasingly wary of China's expanding military activities, especially those with territorial claims that overlap those of Beijing.

ASEAN and China have long been negotiating the maritime code of conduct in the South China Sea to help avert confrontation between the disputants.

In an apparent effort to avoid irritating China, the just-started exercises, which were initially planned to take place in more northerly waters, were moved south.

ASEAN members have conducted joint military exercises with the United States and China, respectively, but there have not been joint drills involving only the bloc until now.

Indonesia has also recently hosted a military drill -- Super Garuda Shield -- with thousands of troops from the United States, Japan, Australia, France, Singapore and Britain taking part.

ASEAN comprises Brunei, Cambodia, Indonesia, Laos, Malaysia, Myanmar, the Philippines, Singapore, Thailand and Vietnam.

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